Amino methylated 2-pyridinones

ABSTRACT

Novel amino methylated 2-pyridinones, precursors, intermediates, and derivatives; the methods for the preparation of the same; uses of the same for inhibiting pili formation in bacteria; and pharmaceutical compositions comprising these compounds are described in this application. The present compounds may be employed to inhibit biofilm formation and thereby inhibit adherence of bacteria to a host cell.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No. 11/581,518, filed Oct. 16, 2006, which is a continuation in part of International Patent Application Serial No. PCT/US2005/013032, filed Apr. 14, 2005, which claims the benefit of U.S. Provisional Application Ser. No. 60/563,082, filed Apr. 16, 2004, the entire content of each of which is hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention is directed to secondary and tertiary amino methylated 2-pyridinones, to methods of their preparation and to their use for inhibiting pili formation in bacteria.

The core structure of 2-pyridinones, or more commonly referred to as 2-pyridones, is present in a wide range of compounds with diverse biological application areas. Besides showing e.g., antibacterial,¹ antifungal² and anti-tumor activity,^(3,4) members of these heterocycles also act as inhibitors of a Aβ-peptide aggregation thought to play an important role in Alzheimers' disease.⁵ An enantioselective ketene imine cycloaddition reaction to synthesize ring fused substituted 2-pyridones has previously been reported.^(6,7) Starting from commercially available nitriles and carboxylic acids, this synthetic pathway rendered a first generation of 2-pyridones that were designed to target periplasmic escort proteins, chaperones, in uropathogenic Escherichia coli. Chaperones are essential for the assembly of adhesive protein organelles known as pili or fimbriae present on the surface of the bacteria, in absence of these organelles the bacteria become non-infectious.⁸ Thus, compounds interfering with pili/fimbriae formation, pilicides, would represent a novel class of antibacterial agents directed against bacterial virulence considered a promising avenue in drug development.⁹

Encouraging affinity predictions of substituted 2-pyridones binding to the chaperones PapD and FimC have previously been confirmed in vitro by direct binding assays using both surface plasmon resonance techniques and NMR spectroscopy, where the corresponding acid of 4a was found to be a potent binder.¹⁰ Recently, efficient improvements of the original synthetic procedure were reported.¹¹ This alternative microwave assisted method allows simple and fast preparation of highly substituted 2-pyridones in good yields and with limited racemization. Still, position six is available for further substitution and thus provides an opportunity to introduce hydrophilic functionalities targeting increased bioavailability and enhanced chaperone affinity in the pilicide project. Incorporation of a cyano group would provide a precursor to a number of interesting derivatives such as carboxylic acids,¹² tetrazoles,¹³ and amidines.¹⁴ Nitriles can also be converted into primary amines and inspired by former observations in drug development this appeared to be an attractive target. For example in the case of Ampicillin and Amoxycillin, the introduction of an amine substituent led to a broad spectrum antibiotic also affecting Gram-negatives.¹⁵ In addition, introducing amine substituents in the 2-pyridone framework would result in highly substituted rigid amino acids, which could serve as versatile scaffolds and peptide mimetics.¹⁶

Aromatic cyanodehalogenation and subsequent reduction of the cyano functionality was considered a well cited and straightforward pathway towards amino methylated 2-pyridones.^(17,18) As a complement to the primary amines, and to expand the chemical diversity of these structures, tertiary amines were also desired. A few scattered examples where 2-pyridones react with imines in a Mannich reaction in the corresponding position have previously been described^(19,20) and recently, microwave mediated Mannich reactions performed with electron-rich aromatic substrates have also been published.^(21,22) Nevertheless, applications on more complex structures such as functionalized 2-pyridones with a challenging substitution pattern have previously not been reported.

SUMMARY OF THE INVENTION

Among the various aspects of the present invention are secondary and tertiary amino methylated 2-pyridinones (and their corresponding salts), methods of their preparation and their use for inhibiting pili formation in bacteria.

Briefly, therefore, the present invention is directed to an amino methylated 2-pyridinone corresponding to Formula I or a salt thereof:

wherein:

R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or in combination with the nitrogen atom to which they are bonded, form a heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen;

R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen; and

the “Z” ring contains 5 to 7 ring atoms selected from the group consisting of carbon, oxygen, nitrogen and sulfur, provided (i) at least 4 of the ring atoms are carbon when the “Z” ring contains 7 ring atoms, and (ii) at least 3 of the ring atoms are carbon when the “Z” ring contains 5 or 6 ring atoms.

The present invention is further directed to an amino methylated 2-pyridinone corresponding to Formula II or a salt thereof:

wherein:

R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or in combination with the nitrogen atom to which they are bonded, form a heterocyclo provided at least one of R₂ and R₃ is other than hydrogen;

R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen;

X₁ is a bond, carbon, oxygen, nitrogen, or sulfur;

X₂ is a bond, carbon, oxygen, nitrogen, or sulfur;

X₃ and X₄ are independently carbon, oxygen, nitrogen, or sulfur;

X₅ is carbon or nitrogen;

each X₁₁, when present, is an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo;

each X₂₂, when present, is an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo;

each X₃₃ and X₄₄ is independently an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo;

X₅₅ is —CH₂OX₅₅₅, —CH(CO₂X₅₅₅)₂, —CH₂CO₂X₅₅₅, —CO₂X₅₅₅, —CHO, —B(OH)₂, or —PO(OH)₂; and

X₅₅₅ is hydrogen or other cation, hydrocarbyl, substituted hydrocarbyl, or heterocyclo;

provided, however, (i) X₁₁ or X₂₂ is not present when X₁ or X₂ is a bond; and (ii) X₁, X₂, X₃, and X₄ are not oxygen, nitrogen or sulfur when X₅ is nitrogen.

The present invention is further directed to a compound having the formula

wherein R1, R2, and R3, in combination, are selected from the combinations identified in the following table as combinations 8a-8f:

Combination No. R¹ R² R³ 8a phenyl methyl NMe₂ 8b phenyl methyl morpholine 8c phenyl CH₂-1-naphtyl NMe₂ 8d phenyl CH₂-1-naphtyl morpholine 8e cyclopropyl CH₂-1-naphtyl NMe₂ 8f^(c) cyclopropyl CH₂-1-naphtyl morpholine

The present invention is further directed to amino methylated 2-pyridinones corresponding to one or more of Formulae III-VIII (which appear elsewhere herein) or a salt thereof.

The present invention is further directed to a method for the preparation of an amino methylated 2-pyridinone or a salt thereof, the process comprising forming a reaction mixture comprising a 2-pyridinone and an iminium salt, allowing the 2-pyridinone and iminium salt to react to form, via a Mannich reaction, an amino methylated 2-pyridinone corresponding to any of Formulae I-VIII (which appear elsewhere herein), wherein the nitrogen atom of the amino methyl substituent is a tertiary amine.

The present invention is further directed to a method for the preparation of an amino methylated 2-pyridinone or a salt thereof, the process comprising forming a reaction mixture comprising a 2-pyridinone and an iminium salt, allowing the 2-pyridinone and iminium salt to react to form, via a Mannich reaction, an amino methylated 2-pyridinone corresponding to any of Formulae I-VIII (which appear elsewhere herein), wherein the nitrogen atom of the amino methyl substituent is a tertiary amine, and wherein the reaction mixture is irradiated with microwaves.

The present invention is further directed to a method for the preparation of an amino methylated 2-pyridinone or a salt thereof, the process comprising reacting a 2-pyridinone and reducing the formyl substituted 2-pyridinone to form an amino methylated 2-pyridinone corresponding to any of Formulae I-VIII (which appear elsewhere herein), wherein the nitrogen atom of the amino methyl substituent is a secondary amine.

The present invention is further directed to a process for inhibiting adherence of bacteria to a host cell, the process comprising treating the bacteria with a compound of any of Formulae I-VIII (which appear elsewhere herein) or a salt thereof.

The present invention is further directed to a process for inhibiting adherence of bacteria to a host cell, wherein the host cell is in a cell culture and the bacteria is treated by introducing a compound of any of Formula I-VIII (which appear elsewhere herein) or a salt thereof to the cell culture.

Other objects and features of this invention will be in part apparent and in part pointed out hereinafter.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention, processes have been developed enabling the preparation of secondary and tertiary amino methylated 2-pyridiones. These 2-pyridinones have been found to inhibit or even prevent bacterial infection of host cells by interrupting the formation of pili. Thus, for example, these 2-pyridinones may be employed to inhibit biofilm formation and thereby inhibit adherence of the bacteria to a host cell; this may be accomplished when the composition interferes with the function of chaperones required for the assembly of pili from pilus subunits in diverse Gram-negative bacteria. Such interference is particularly effective since the formation of pili is essential to bacterial pathogenicity and since the production of the pilus subunits in the absence of chaperones is known to be directly toxic.

1. Amino Methylated 2-Pyridinone Compositions

In general, the secondary or tertiary amino methylated 2-pyridinones correspond to Formula 1 or a salt thereof:

wherein

R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or, in combination with the nitrogen atom to which they are bonded, form a heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen;

R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen; and

the “Z” ring contains 5 to 7 ring atoms selected from the group consisting of carbon, oxygen, nitrogen and sulfur, provided (i) at least 4 of the ring atoms are carbon when the “Z” ring contains 7 ring atoms, and (ii) at least 3 of the ring atoms are carbon when the “Z” ring contains 5 or 6 ring atoms.

As previously noted, R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or, in combination with the nitrogen atom to which they are bonded, form a heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen (i.e., at least one of R₂ and R₃ is hydrocarbyl, substituted hydrocarbyl or heterocyclo). When one and only one of R₂ and R₃ is hydrogen, the 2-pyridinone is characterized herein as a secondary amino methylated 2-pyridinone. When neither of R₂ and R₃ are hydrogen, the 2-pyridinone is characterized herein as a tertiary amino methylated 2-pyridinone.

In one embodiment, the 2-pyridinone is a secondary amino methylated 2-pyridinone and one of R₂ and R₃ is hydrocarbyl or substituted hydrocarbyl. In this embodiment, for example, R₂ or R₃ may be alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as alkaryl. In general, when R₂ or R₃ is alkyl, C1 to C6 alkyls are typically preferred. For example, R₂ or R₃ may be methyl, ethyl, propyl (straight, branched or cyclic), butyl (straight, branched or cyclic), pentyl, (straight, branched or cyclic), or hexyl (straight, branched or cyclic). Alternatively, R₂ or R₃ may be substituted alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as substituted alkaryl. For example, R₂ or R₃ may be substituted methyl, substituted ethyl, substituted propyl (straight, branched or cyclic), substituted butyl (straight, branched or cyclic), substituted pentyl, (straight, branched or cyclic), or substituted hexyl (straight, branched or cyclic) wherein the substituent(s) is/are selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. In one such embodiment R₂ or R₃ may be heterocyclo or alkyl.

Alternatively, the 2-pyridinone may be a secondary amino methylated 2-pyridinone and one of R₂ and R₃ is heterocyclo. In this embodiment, for example, R₂ or R₃ may be a 5 or 6-membered heterocycle which is saturated, partially unsaturated or fully unsaturated; in addition, the ring atoms of the heterocycle may be further substituted. Exemplary 5 and 6-membered heterocycles include furyl, thienyl, pyridyl, oxazolyl, isoxazolyl, pyrrolyl, indolyl, quinolinyl, and isoquinolinyl. In one embodiment, for example, the heterocycle may be optionally substituted indolyl, furyl, or pyrrolyl. If substituted, the 5 or 6-membered ring may have one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties.

The 2-pyridinone may alternatively be a tertiary amino methylated 2-pyridinone with R₂ and R₃ independently being selected from hydrocarbyl, substituted hydrocarbyl, and heterocyclo. For example, one of R₂ and R₃ may be hydrocarbyl or substituted hydrocarbyl when the other of R₂ and R₃ is heterocyclo. Similarly, one of R₂ and R₃ may be hydrocarbyl when the other is substituted hydrocarbyl. In each of these embodiments, R₂ and R₃, the hydrocarbyl, substituted hydrocarbyl, and/or heterocyclo groups may be any of the moieties previously described for R₂ or R₃ in the embodiment in which the 2-pyridinone is a secondary amino methylated 2-pyridinone. For example, R₂ and/or R₃ may be alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as alkaryl. In general, when R₂ and/or R₃ is alkyl, C1 to C6 alkyls are typically preferred. Thus, R₂ and/or R₃ may be methyl, ethyl, propyl (straight, branched or cyclic), butyl (straight, branched or cyclic), pentyl, (straight, branched or cyclic), or hexyl (straight, branched or cyclic). Alternatively, R₂ and/or R₃ may be substituted alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as substituted alkaryl. For example, R₂ and/or R₃ may be substituted methyl, substituted ethyl, substituted propyl (straight, branched or cyclic), substituted butyl (straight, branched or cyclic), substituted pentyl, (straight, branched or cyclic), or substituted hexyl (straight, branched or cyclic) wherein the substituent(s) is/are selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. By way of further example, R₂ and/or R₃ may be a 5 or 6-membered heterocycle which is saturated, partially unsaturated or fully unsaturated. Exemplary 5 and 6-membered heterocycles include furyl, thienyl, pyridyl, oxazolyl, isoxazolyl, pyrrolyl, indolyl, quinolinyl, and isoquinolinyl. In one such embodiment, the 5 or 6-membered ring is unsubstituted. In another embodiment, the 5 or 6-membered ring has one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. In general, when R₂ and/or R₃ is aryl monocyclic or bicyclic groups containing from 6 to 12 carbons in the ring portion are typically preferred. Thus, R₂ and/or R₃ may be phenyl, biphenyl, naphthyl, substituted phenyl, substituted biphenyl or substituted naphthyl.

In a further embodiment, the 2-pyridinone is a tertiary amino methylated 2-pyridinone with R₂, R₃ and the nitrogen atom to which they are each bonded defining a nitrogen-containing heterocyclo. In this embodiment, for example, R₂, R₃ and the nitrogen atom to which they are each bonded define a 5- or 6-membered nitrogen-containing ring such as substituted morpholine, piperidine, or 2- or 4-pyrrolidine. Optionally, the heterocyclo ring is substituted by one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties

In a further embodiment of the amino methylated 2-pyridinone, (i) R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl or heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen and (ii) each X₁₁, when present, is an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo.

In general, R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen (i.e., at least one of R₄ and R₅ is hydrocarbyl, substituted hydrocarbyl or heterocyclo). For example, R₄ may be hydrocarbyl, substituted hydrocarbyl or heterocyclo when R₅ is hydrogen. Alternatively, R₅ may be hydrocarbyl, substituted hydrocarbyl or heterocyclo when R₄ is hydrogen. In another embodiment, each of R₄ and R₅ are selected independently from hydrocarbyl, substituted hydrocarbyl and heterocyclo. That is, one of R₄ and R₅ may be hydrocarbyl or substituted hydrocarbyl when the other of R₄ and R₅ is heterocyclo. Similarly, one of R₄ and R₅ may be hydrocarbyl when the other is substituted hydrocarbyl. In each of these embodiments, the hydrocarbyl, substituted hydrocarbyl, and/or heterocyclo groups may be any of the moieties previously described for R₂ and R₃. In one presently preferred embodiment, each of R₄ and R₅ is hydrocarbyl. For example, one of R₄ and R₅ may be aryl (e.g., phenyl or naphthyl) when the other is alkyl. In general, when R₄ and/or R₅ is alkyl, C3 to C15 alkyls are typically preferred. For example, when R₄ and/or R₅ is alkyl, one or both substituents may be methyl, ethyl, propyl, isopropyl, butyl, hexyl, octyl, nonyl, undecyl, dodecyl and the like. Alternatively, one of R₄ and R₅ may be phenyl when the other is naphthyl.

As depicted in Formula 1, the “Z” ring, together with the “Y” ring forms a fused, bicyclic ring system. As depicted, the “Y” ring contains six ring atoms with one of the ring atoms being nitrogen. As previously defined, the “Z” ring contains 5 to 7 ring atoms, with two of these 5 to 7 ring atoms (i.e., one nitrogen and one carbon atom) also being part of the “Y” ring. The remaining atoms of the “Z” ring are selected from the group consisting of carbon, oxygen, nitrogen, and sulfur, provided, however, when the “Z” ring is a 6 or 7-membered ring, no more than three ring atoms of the “Z” ring are oxygen, nitrogen, or sulfur, or a combination thereof and when the “Z” ring is a 5-membered ring, no more than two ring atoms of the “Z” ring are oxygen, nitrogen, or sulfur, or a combination thereof. Stated another way, when the “Z” ring is a 6 or 7-membered ring, in addition to the nitrogen atom which is shared by the X and Y rings, two additional ring atoms in the “Z” ring may be selected from oxygen, nitrogen and sulfur and when the “Z” ring is a 5-membered ring, in addition to the nitrogen atom which is shared by the X and Y rings, one additional ring atom in the “Z” ring may be selected from oxygen, nitrogen and sulfur.

In one such embodiment, the “Z” ring is a 5, 6 or 7-membered saturated or partially unsaturated ring. For example, in this embodiment the compound may correspond to Formula II:

wherein

R₂, R₃, R₄, and R₅ are as defined in connection with Formula I and each of the permutations thereof;

X₁ is a bond, carbon, oxygen, nitrogen, or sulfur;

X₂ is a bond, carbon, oxygen, nitrogen, or sulfur;

X₃ and X₄ are independently carbon, oxygen, nitrogen, or sulfur;

X₅ is carbon or nitrogen;

each X₁₁, when present, is an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, oxo, halo, or acyl;

each X₂₂, when present, is an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo;

each X₃₃ and X₄₄ is independently an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo;

X₅₅ is —CH₂OX₅₅₅, —CH(CO₂X₅₅₅)₂, —CH₂CO₂X₅₅₅, —CO₂X₅₅₅, —CHO, —B(OH)₂, or —PO(OH)₂; and

X₅₅₅ is hydrogen or other cation, hydrocarbyl, substituted hydrocarbyl, or heterocyclo;

provided, however, (i) X₁₁ or X₂₂ is not present when X₁ or X₂, respectively, is a bond; (ii) no more than two of X₁, X₂, X₃, X₄ and X₅ are oxygen, nitrogen or sulfur when the “Z” ring contains 6 or 7 ring atoms, and (iii) no more than one of X₁, X₂, X₃, X₄ and X₅ are oxygen, nitrogen or sulfur when the “Z” ring contains 5 ring atoms.

In this embodiment, R₂, R₃, R₄, and R₅ may be present in each of the permutations previously described in connection with Formula I. For example, the compound corresponding to Formula II, or salt thereof, may be a secondary amino methylated 2-pyridinone (wherein one, but only one of R₂ and R₃ is hydrogen); in this embodiment, one of R₂ and R₃ is hydrocarbyl, substituted hydrocarbyl or heterocyclo with the hydrocarbyl, substituted hydrocarbyl or heterocyclo being as described in connection with Formula I. Alternatively, the compound corresponding to Formula II, or salt thereof, may be a tertiary amino methylated 2-pyridinone (wherein neither R₂ or R₃ is hydrogen); in this embodiment, each of R₂ and R₃ are independently hydrocarbyl, substituted hydrocarbyl or heterocyclo with the hydrocarbyl, substituted hydrocarbyl or heterocyclo moieties and each of the possible permutations thereof being as described in connection with Formula I.

As depicted, the “Z” ring, i.e., the ring defined by X₁-X₅ and the carbon and nitrogen atoms to which X₁ and X₅, respectively, are bonded, may be a five, six or seven-membered ring. When the “Z” ring is a seven-membered ring, neither X₁ nor X₂ is a bond. When the “Z” ring is a six-membered ring, however, X₁ is a bond directly linking X₂ to the carbon atom of the other ring of the fused bicyclic system (i.e., the ring designated as the “Y” ring in Formula I). When the “Z” ring is a five-membered ring, X₁ and X₂, in combination, define a bond directly linking X₃ to the carbon atom of the other ring of the fused bicyclic system (i.e., the ring designated as the “Y” ring in Formula I). When the “Z” ring is a six-membered ring, therefore, neither X₁₁ is present since the ring atom to which each X₁₁ is shown as being a substituent is not present. Similarly, when the “Z” ring is a five-membered ring, neither of the X₁₁ substituents nor either of the X₁₂ substituents is present since the ring atoms to which they are shown as being attached are not present.

As depicted in Formula II, X₁-X₅ are substituted by two X₁₁-X₅₅ substituents, respectively. As defined, each X₁₁-X₅₅ may be an electron pair; for example, one or more of X₁₁-X₅₅ may be an electron pair when two or more of X₁-X₅ are not fully saturated, e.g., an sp² hybridized carbon. Alternatively, one or more of X₁₁-X₅₅ may be an electron pair when one of X₁-X₅ is oxygen, sulfur or nitrogen. Thus, for example, one of X₁-X₅ may be a saturated nitrogen atom bonded to two other ring atoms and a corresponding substituent designated X₁₁-X₅₅ (depending upon the ring position of nitrogen atom) with the other corresponding substituent designated X₁₁-X₅₅ being an electron pair of the nitrogen atom. Also, it is contemplated that a sulfur or ring nitrogen atom may be in any of their available oxidation states. For example, a ring sulfur atom may be in sulfide oxidation state (—S—), the sulfoxide oxidation state (—SO—), or the sulfone oxidation state (—SO₂—). Similarly, a ring nitrogen atom may be in its N-oxide oxidation state (—N(═O)—). For example, if X₁ is sulfur, each X₁₁ may be an electron pair (which corresponds to the sulfide oxidation state), one X₁₁ may be an electron pair when the other is oxo (which corresponds to sulfoxide oxidation state) or each X₁₁ may be oxo (which corresponds to the sulfone oxidation state).

In one embodiment, X₅₅ is an acyl or acyl-containing moiety. For example, in this embodiment X₅₅ may be —CH(CO₂X₅₅₅)₂, —CH₂CO₂X₅₅₅, —CO₂X₅₅₅, or —CHO. In a further embodiment, X₅₅ may be —CH(CO₂X₅₅₅)₂. In general, X₅₅₅ is preferably hydrogen or another cation such as an alkali metal, an alkaline earth metal or ammonium in this embodiment. In another embodiment, X₅₅ may be —CH(CO₂X₅₅₅)₂, —CH₂CO₂X₅₅₅, or —CO₂X₅₅₅. In another embodiment, X₅₅ may be —CH(CO₂X₅₅₅)₂ or —CH₂CO₂X₅₅₅. In still another embodiment, X₅₅ may be —CH(CO₂X₅₅₅)₂. In a further embodiment, X₅₅ is —B(OH)₂, —PO(OH)₂, or tetrazole.

While the “Z” ring may be seven-membered in one embodiment, it is presently preferred that the “Z” ring be a five or six-membered ring. In this embodiment, the secondary or tertiary amino methylated 2-pyridinone corresponds to Formula III:

wherein R₂, R₃, R₄, R₅, X₂, X₃, X₄, X₅, X₂₂, X₃₃, X₄₄, and X₅₅ are as described in connection with Formula II and each of the permutations thereof. In one embodiment, X₃₃ and X₄₄ is independently an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, oxo, halo or acyl.

Still more preferably, the “Z” ring is a 5-membered ring. For example, in this embodiment, the secondary or tertiary amino methylated 2-pyridinone compound corresponds to Formula IV:

wherein R₂, R₃, R₄, R₅, X₃, X₄, X₅, X₃₃, X₄₄, and X₅₅ are as described in connection with Formula II and each of the permutations thereof. In one embodiment, each X₄₄ is independently an electron pair, hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, oxo, halo or acyl.

When the secondary or tertiary amino methylated 2-pyridinone compound corresponds to Formula IV and X₄ is carbon, a chiral center may exist at the ring position occupied by X₅. Thus, for example, isomers corresponding to Formula Va and Vb may exist:

wherein R₂, R₃, R₄, R₅, X₃, X₅, X₃₃, X₄₄, and X₅₅ are as described in connection with Formula II and each of the permutations thereof. In one embodiment, the secondary or tertiary amino methylated 2-pyridinone compound corresponds to Formula Va. In another embodiment, the secondary or tertiary amino methylated 2-pyridinone compound corresponds to Formula Vb. In another embodiment, each X₄₄ is hydrogen, hydrocarbyl, halo or acyl.

In one preferred embodiment of the present invention, the “Z” ring is a 5-membered ring containing a sulfur atom. For example, in this embodiment, the compound may correspond to Formula VIa or VIb:

wherein R₂, R₃, R₄, R₅, X₅, X₃₃, X₄₄, and X₅₅ are as described in connection with Formula II and each of the permutations thereof.

In one embodiment in which the secondary or tertiary amino methylated 2-pyridinone corresponds to Formula VI, sulfur is in the sulfide oxidation state (i.e., each X₃₃ is an electron pair). In another such embodiment, sulfur is in the sulfoxide oxidation state (i.e., one X₃₃ is an electron pair and the other is oxo (═O)). In yet another such embodiment, sulfur is in the sulfone oxidation state (i.e., each X₃₃ is oxo (═O)). In yet another embodiment, X₄₄ is hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, oxo, halo or acyl. In still another embodiment, X₄₄ is hydrogen, alkyl, halo, —C(O)R₄₄ or —C(O)N(R₄₄)₂ and each R₄₄ is independently hydrogen, alkyl or aryl. In another embodiment, X₅₅ is —CO₂X₅₅₅. In yet another embodiment, X₅₅₅ may be hydrogen, alkyl, or an alkaline metal. In still another embodiment, (i) R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl or heterocyclo, and (ii) X₄₄ is hydrogen, hydrocarbyl, substituted hydrocarbyl, heterocyclo, or oxo. In yet another embodiment, R₂ is alkyl. In another embodiment, R₂ and R₃, in combination with the nitrogen atom to which they are bonded from a heterocyclo. In another embodiment, R₄ is alkyl or aryl. In another embodiment, R₅ is alkyl.

When the secondary or tertiary amino methylated 2-pyridinone corresponds to Formula VI, X₄₄ may have any of the values previously described for X₄₄. Typically, however, X₄₄ will be hydrogen or hydrocarbyl. More typically, X₄₄ will be hydrogen.

In one preferred embodiment of the present invention, the “Z” ring is a saturated 5-membered ring. For example, in this embodiment, the compound may correspond to Formula VIIa or VIIb:

wherein R₂, R₃, R₄, R₅, X₃₃, and X₅₅ are as described in connection with Formula II and each of the permutations thereof.

When the secondary or tertiary amino methylated 2-pyridinone corresponds to Formula VIIa or VIIb, the sulfur atom may be in the sulfide oxidation state (i.e., each X₃₃ is an electron pair). Alternatively, the sulfur atom may be in the sulfoxide oxidation state (i.e., one X₃₃ is an electron pair and the other is oxo (═O)). The sulfur atom may also be in the sulfone oxidation state (i.e., each X₃₃ is oxo (═O)).

In one embodiment, the 2-pyridinone corresponds to Formula VIIa or VIIb, one of R₂ and R₃ is hydrogen and the other is hydrocarbyl or substituted hydrocarbyl. In this embodiment, for example, one of R₂ or R₃ is hydrogen and the other is alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as alkaryl. For example, R₂ or R₃ may be optionally substituted methyl, ethyl, propyl (straight, branched or cyclic), butyl (straight, branched or cyclic), pentyl, (straight, branched or cyclic), or hexyl (straight, branched or cyclic) wherein the substituent(s) is/are selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. In one such embodiment R₂ or R₃ may be heterocyclo or alkyl.

Alternatively, the 2-pyridinone may correspond to Formula VIIa or VIIb wherein one of R₂ and R₃ is hydrogen and the other is heterocyclo. In this embodiment, for example, R₂ or R₃ may be optionally substituted furyl, thienyl, pyridyl, oxazolyl, isoxazolyl, pyrrolyl, indolyl, quinolinyl, and isoquinolinyl. In one particular embodiment, for example, the heterocycle may be optionally substituted indolyl, furyl, or pyrrolyl. If substituted, the 5 or 6-membered ring may have one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties.

The 2-pyridinone may alternatively correspond to Formula VIIa or VIIb wherein each of R₂ and R₃ are independently selected from hydrocarbyl, substituted hydrocarbyl, and heterocyclo. For example, one of R₂ and R₃ may be hydrocarbyl or substituted hydrocarbyl when the other of R₂ and R₃ is heterocyclo. Similarly, one of R₂ and R₃ may be hydrocarbyl when the other is substituted hydrocarbyl. In each of these embodiments, the R₂ and R₃ hydrocarbyl, substituted hydrocarbyl, and/or heterocyclo groups may be any of the moieties previously described for R₂ or R₃ in connection with Formulae VIIa and VIIb, and the various permutations thereof. For example, R₂ and/or R₃ may be alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as alkaryl. In general, when R₂ and/or R₃ is alkyl, C1 to C6 alkyls are typically preferred. Thus, R₂ and/or R₃ may be methyl, ethyl, propyl (straight, branched or cyclic), butyl (straight, branched or cyclic), pentyl, (straight, branched or cyclic), or hexyl (straight, branched or cyclic). Alternatively, R₂ and/or R₃ may be substituted alkyl, alkenyl, alkynyl, aryl, or a combination thereof such as substituted alkaryl. For example, R₂ and/or R₃ may be substituted methyl, substituted ethyl, substituted propyl (straight, branched or cyclic), substituted butyl (straight, branched or cyclic), substituted pentyl, (straight, branched or cyclic), or substituted hexyl (straight, branched or cyclic) wherein the substituent(s) is/are selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. By way of further example, R₂ and/or R₃ may be a 5 or 6-membered heterocycle which is saturated, partially unsaturated or fully unsaturated. Exemplary 5 and 6-membered heterocycles include furyl, thienyl, pyridyl, oxazolyl, isoxazolyl, pyrrolyl, indolyl, quinolinyl, and isoquinolinyl, In one such embodiment, the 5 or 6-membered ring is unsubstituted. In another embodiment, the 5 or 6-membered ring has one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties. By way of further example, one of R₂ and/or R₃ may be optionally substituted aryl when the other is hydrocarbyl, substituted hydrocarbyl or heterocyclo wherein the hydrocarbyl, substituted hydrocarbyl or heterocyclo moieties may be as previously described in connection with R₂ and/or R₃.

In a further embodiment, the 2-pyridinone is a tertiary amino methylated 2-pyridinone with R₂, R₃ and the nitrogen atom to which they are each bonded defining a nitrogen-containing heterocyclo. In this embodiment, for example, R₂, R₃ and the nitrogen atom to which they are each bonded define a 5- or 6-membered nitrogen-containing ring such as morpholino, pyrrolyl, or piperidine. Optionally, the heterocyclo ring is substituted by one or more substituents selected from the group consisting of heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, keto, acyloxy, nitro, amino, amido, thiol, ketal, acetal, ester and ether moieties.

In general, R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen (i.e., at least one of R₄ and R₅ is hydrocarbyl, substituted hydrocarbyl or heterocyclo). For example, R₄ may be hydrocarbyl, substituted hydrocarbyl or heterocyclo when R₅ is hydrogen. Alternatively, R₅ may be hydrocarbyl, substituted hydrocarbyl or heterocyclo when R₄ is hydrogen. In another embodiment, each of R₄ and R₅ are selected independently from hydrocarbyl, substituted hydrocarbyl and heterocyclo. That is, one of R₄ and R₅ may be hydrocarbyl or substituted hydrocarbyl when the other of R₄ and R₅ is heterocyclo. Similarly, one of R₄ and R₅ may be hydrocarbyl when the other is substituted hydrocarbyl. In each of these embodiments, the hydrocarbyl, substituted hydrocarbyl, and/or heterocyclo groups may be any of the moieties previously described for R₂ and R₃. In one presently preferred embodiment, each of R₄ and R₅ is hydrocarbyl. For example, one of R₄ and R₅ may be aryl (e.g., phenyl or naphthyl) when the other is alkyl. In general, when R₄ and/or R₅ is alkyl, C3 to C15 alkyls are typically preferred. Alternatively, one of R₄ and R₅ may be phenyl when the other is naphthyl.

In another preferred embodiment of the present invention, the “Z” ring is a saturated 5-membered ring. For example, in this embodiment, the compound may correspond to Formula VIIIa or VIIIb:

wherein R₂, R₃, R₄, R₅, and X₅₅ are as described in connection with Formula II and each of the permutations thereof.

The compounds corresponding to Formulae I-VIII and the salts thereof may have one or more asymmetric carbons and thus, the compositions may exist in diastereomeric, racemic or optically active forms. All of these stereoisomers are contemplated within the scope of the present invention. More particularly, the present invention includes the enantiomers, diastereomers, racemic mixtures and other mixtures thereof.

The compounds corresponding to Formula I-VIII may be in the form of free bases or pharmaceutically acceptable acid addition salts or other salts thereof. The term “pharmaceutically-acceptable salts” embraces salts commonly used to form alkali metal salts and to form addition salts of free acids or free bases. The nature of the salt may vary, provided that it is pharmaceutically-acceptable. Suitable pharmaceutically-acceptable acid addition salts of compounds for use in the present methods may be prepared from an inorganic acid or from an organic acid. Examples of such inorganic acids are hydrochloric, hydrobromic, hydroiodic, nitric, carbonic, sulfuric and phosphoric acid. Appropriate organic acids may be selected from aliphatic, cycloaliphatic, aromatic, araliphatic, heterocyclic, carboxylic and sulfonic classes of organic acids, examples of which are formic, acetic, propionic, succinic, glycolic, gluconic, lactic, malic, tartaric, citric, ascorbic, glucuronic, maleic, fumaric, pyruvic, aspartic, glutamic, benzoic, anthranilic, mesylic, 4-hydroxybenzoic, phenylacetic, mandelic, embonic (pamoic), methanesulfonic, ethanesulfonic, benzenesulfonic, pantothenic, 2-hydroxyethanesulfonic, toluenesulfonic, sulfanilic, cyclohexylaminosulfonic, stearic, algenic, β-hydroxybutyric, salicylic, galactaric and galacturonic acid. Suitable pharmaceutically-acceptable base addition salts of compounds of use in the present methods include metallic salts made from aluminum, calcium, lithium, magnesium, potassium, sodium and zinc or organic salts made from N,N′-dibenzylethylenediamine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine (N-methylglucamine) and procaine. All of these salts may be prepared by conventional means from the corresponding compound by reacting, for example, the appropriate acid or base with the compound of any Formula set forth herein.

2. Synthetic Processes

In general, tertiary amino methylated 2-pyridinones may be prepared via the Mannich reaction using the corresponding 2-pyridinone and an iminium salt according to the following reaction scheme: 2-pyridinone+H₂C═R₃₀ ⁺X⁻

aminomethylated2-pyridinone

wherein the amino methylated 2-pyridinone corresponds to any of Formulae I-VIII described above, R₃₀ ⁺ is a disubstituted quaternary nitrogen atom, X⁻ is a halide and the 2-pyridinone corresponds to any of Formulae I-VIII described above, except that the 2-pyridinone lacks the aminomethyl substituent. Thus, for example, in one embodiment the tertiary amino methylated 2-pyridinone corresponding to Formula I may be prepared according to the following reaction scheme:

wherein R₂, R₃, R₄, and R₅ are as defined in connection with Formula I, X⁻ is a halide, preferably chloride or iodide, and R₃₀ ⁺ is a disubstituted quaternary nitrogen atom with the substituents of the nitrogen atom corresponding to R₂ and R₃. Alternatively, therefore, the iminium salt may be represented by the formula H₂C═N(R₂)(R₃)⁺X⁻ wherein X⁻ is a halide, and R₂ and R₃ are as previously defined. Thus, in one embodiment, R₂ and R₃ may each be alkyl; for example, R₂ and R₃ may each be methyl, ethyl and the like. Alternatively, R₂ and R₃ may, in combination with the ammonium nitrogen atom to which they are attached, define a nitrogen-containing 5 or 6-membered ring such as morpholino, pyrrolyl, or piperidine.

In general, the reaction may be carried out over a range of temperatures and in a range of solvents in which the reactants are soluble. Exemplary solvents include acetonitrile, toluene, N-methyl-2-pyrrolidinone, dimethylformamide, dichloroethane and dichloromethane. Typically, the reaction will be carried out at a temperature in excess of 60° C., preferably at a temperature in excess of 100° C.

To potentially reduce reaction times and/or increase yields, the reaction mixture may be irradiated with microwaves. In general, the microwaves preferably have a wavelength of 1 mm-1 m corresponding and a power of 0.3-300 Ghz. Typically, the microwaves have a wavelength of 12.2 cm and a power of 2.45 Ghz. The reaction mixture may be irradiated for a period from seconds to minutes, with irradiation times typically being in the range of about four minutes to about fourteen minutes. During irradiation, the reaction mixture is preferably maintained at a temperature of about 80° C. to about 180° C., more preferably about 130° C. to about 150° C.

Secondary amino methylated 2-pyridinone may be prepared in a somewhat similar manner, except that a halogenated iminium salt is substituted for the iminium salt in the first reaction step. This produces a formyl substituted pyridinone which can be reductively aminated using a reducing agent and an amine according to the following reaction scheme:

wherein the amino methylated 2-pyridinone corresponds to any of Formulae I-VIII described above, R₃₀ ⁺ is a disubstituted quaternary nitrogen atom, X is halogen and the 2-pyridinone corresponds to any of Formulae I-VIII described above, except that the 2-pyridinone lacks the aminomethyl substituent. Thus, for example, in one embodiment the tertiary amino methylated 2-pyridinone corresponding to Formula I may be prepared according to the following reaction scheme:

wherein R₂, R₃, R₄, and R₅ are as defined in connection with Formula I, X is halogen, preferably chloride or iodine, R₃₀ ⁺ is a quaternary nitrogen atom, and the amine is a secondary amine represented by the formula NHR₂R₃, wherein R₂ and R₃ are as described above. Thus, in one embodiment, R₂ and R₃ may each be alkyl; for example, R₂ and R₃ may each be methyl, ethyl and the like. Alternatively, R₂ and R₃ may, in combination with the ammonium nitrogen atom to which they are attached, define a nitrogen-containing 5 or 6-membered ring such as morpholino, pyrrolyl, or piperidine.

In general, the reducing agent may be any conventional reducing agent, provided the reducing agent does not undesirably reduce other substituents in the molecule. Preferably a nucleophilic reducing agent is used. For example, under appropriate conditions the reducing agent may be H₂ gas and an organometalic. In general, borohydrides such as sodium borohydrides or sodium 3-acetoxy borohydride are preferred. Alternatively, a borohydride such as sodium cyanoborohydride may be used.

The reaction may be carried out over a range of temperatures and in a range of solvents in which the reactants are soluble. Exemplary solvents include acetonitrile, toluene, N-methyl-2-pyrrolidinone, dimethylformamide, and dichloroethane. Typically, the reaction will be carried out at a temperature in excess of 0° C., preferably at a temperature in excess of 20° C.

3. Uses

Compounds corresponding to any of Formulae I-VIII and the salts thereof may be used in vitro or in vivo to inhibit pili formation by bacteria. Thus, for example, a compound of the present invention or a salt thereof may be introduced to a cell culture to inhibit pili formation. Alternatively, a compound of the present invention or a salt thereof may be administered to a mammal to inhibit pili formation in vivo. In a further alternative, a prosthetic implant may be coated with a compound of the present invention or salt thereof before the prosthesis is implanted in a patient's body.

For in vivo applications, a pharmaceutical composition comprising an effective amount of a compound of the present invention (or salt thereof) in combination with at least one pharmaceutically or pharmacologically acceptable carrier is administered to an animal, including humans. The carrier, also known in the art as an excipient, vehicle, auxiliary, adjuvant, or diluent, is any substance which is pharmaceutically inert, confers a suitable consistency or form to the composition, and does not diminish the therapeutic efficacy of the compounds. The carrier is “pharmaceutically or pharmacologically acceptable” if it does not produce an adverse, allergic or other untoward reaction when administered to a mammal or human, as appropriate.

The pharmaceutical compositions containing the compounds (or salts) of the present invention may be formulated in any conventional manner. Proper formulation is dependent upon the route of administration chosen. The compositions of the invention can be formulated for any route of administration so long as the target tissue is available via that route. Suitable routes of administration include, but are not limited to, oral, parenteral (e.g., intravenous, intraarterial, subcutaneous, rectal, subcutaneous, intramuscular, intraorbital, intracapsular, intraspinal, intraperitoneal, or intrasternal), topical (nasal, transdermal, intraocular), intravesical, intrathecal, enteral, pulmonary, intralymphatic, intracavital, vaginal, transurethral, intradermal, aural, intramammary, buccal, orthotopic, intratracheal, intralesional, percutaneous, endoscopical, transmucosal, sublingual and intestinal administration.

Pharmaceutically acceptable carriers for use in the compositions of the present invention are well known to those of ordinary skill in the art and are selected based upon a number of factors: the particular compound used, and its concentration, stability and intended bioavailability; the disease, disorder or condition being treated with the composition; the subject, its age, size and general condition; and the route of administration. Suitable carriers are readily determined by one of ordinary skill in the art (see, for example, J. G. Nairn, in: Remington's Pharmaceutical Science (A. Gennaro, ed.), Mack Publishing Co., Easton, Pa., (1985), pp. 1492-1517, the contents of which are incorporated herein by reference).

The compositions are preferably formulated as tablets, dispersible powders, pills, capsules, gelcaps, caplets, gels, liposomes, granules, solutions, suspensions, emulsions, syrups, elixirs, troches, dragees, lozenges, or any other dosage form which can be administered orally. Techniques and compositions for making oral dosage forms useful in the present invention are described in the following references: 7 Modern Pharmaceutics, Chapters 9 and 10 (Banker & Rhodes, Editors, 1979); Lieberman et al., Pharmaceutical Dosage Forms: Tablets (1981); and Ansel, Introduction to Pharmaceutical Dosage Forms 2nd Edition (1976).

The compositions of the invention for oral administration comprise an effective amount of a compound of the invention in a pharmaceutically acceptable carrier. Suitable carriers for solid dosage forms include sugars, starches, and other conventional substances including lactose, talc, sucrose, gelatin, carboxymethylcellulose, agar, mannitol, sorbitol, calcium phosphate, calcium carbonate, sodium carbonate, kaolin, alginic acid, acacia, corn starch, potato starch, sodium saccharin, magnesium carbonate, tragacanth, microcrystalline cellulose, colloidal silicon dioxide, croscarmellose sodium, talc, magnesium stearate, and stearic acid. Further, such solid dosage forms may be uncoated or may be coated by known techniques; e.g., to delay disintegration and absorption.

The compounds and salts of the present invention may also be formulated for parenteral administration, e.g., formulated for injection via intravenous, intraarterial, subcutaneous, rectal, subcutaneous, intramuscular, intraorbital, intracapsular, intraspinal, intraperitoneal, or intrasternal routes. The compositions of the invention for parenteral administration comprise an effective amount of the composition in a pharmaceutically acceptable carrier. Dosage forms suitable for parenteral administration include solutions, suspensions, dispersions, emulsions or any other dosage form which can be administered parenterally. Techniques and compositions for making parenteral dosage forms are known in the art.

Suitable carriers used in formulating liquid dosage forms for oral or parenteral administration include nonaqueous, pharmaceutically-acceptable polar solvents such as oils, alcohols, amides, esters, ethers, ketones, hydrocarbons and mixtures thereof, as well as water, saline solutions, dextrose solutions (e.g., DW5), electrolyte solutions, or any other aqueous, pharmaceutically acceptable liquid.

Suitable nonaqueous, pharmaceutically-acceptable polar solvents include, but are not limited to, alcohols (e.g., α-glycerol formal, β-glycerol formal, 1,3-butyleneglycol, aliphatic or aromatic alcohols having 2-30 carbon atoms such as methanol, ethanol, propanol, isopropanol, butanol, t-butanol, hexanol, octanol, amylene hydrate, benzyl alcohol, glycerin (glycerol), glycol, hexylene glycol, tetrahydrofurfuryl alcohol, lauryl alcohol, cetyl alcohol, or stearyl alcohol, fatty acid esters of fatty alcohols such as polyalkylene glycols (e.g., polypropylene glycol, polyethylene glycol), sorbitan, sucrose and cholesterol); amides (e.g., dimethylacetamide (DMA), benzyl benzoate DMA, dimethylformamide, N-(β-hydroxyethyl)-lactamide, N,N-dimethylacetamide_amides, 2-pyrrolidinone, 1-methyl-2-pyrrolidinone, or polyvinylpyrrolidone); esters (e.g., 1-methyl-2-pyrrolidinone, 2-pyrrolidinone, acetate esters such as monoacetin, diacetin, and triacetin, aliphatic or aromatic esters such as ethyl caprylate or octanoate, alkyl oleate, benzyl benzoate, benzyl acetate, dimethylsulfoxide (DMSO), esters of glycerin such as mono, di, or tri-glyceryl citrates or tartrates, ethyl benzoate, ethyl acetate, ethyl carbonate, ethyl lactate, ethyl oleate, fatty acid esters of sorbitan, fatty acid derived PEG esters, glyceryl monostearate, glyceride esters such as mono, di, or tri-glycerides, fatty acid esters such as isopropyl myristrate, fatty acid derived PEG esters such as PEG-hydroxyoleate and PEG-hydroxystearate, N-methylpyrrolidinone, pluronic 60, polyoxyethylene sorbitol oleic polyesters such as poly(ethoxylated)₃₀₋₆₀ sorbitol poly(oleate)₂₋₄, poly(oxyethylene)₁₅₋₂₀ monooleate, poly(oxyethylene)₁₅₋₂₀ mono 12-hydroxystearate, and poly(oxyethylene)₁₅₋₂₀ mono ricinoleate, polyoxyethylene sorbitan esters such as polyoxyethylene-sorbitan monooleate, polyoxyethylene-sorbitan monopalmitate, polyoxyethylene-sorbitan monolaurate, polyoxyethylene-sorbitan monostearate, and Polysorbate® 20, 40, 60 or 80 from ICI Americas, Wilmington, Del., polyvinylpyrrolidone, alkyleneoxy modified fatty acid esters such as polyoxyl 40 hydrogenated castor oil and polyoxyethylated castor oils (e.g., Cremophor® EL solution or Cremophor® RH 40 solution), saccharide fatty acid esters (i.e., the condensation product of a monosaccharide (e.g., pentoses such as ribose, ribulose, arabinose, xylose, lyxose and xylulose, hexoses such as glucose, fructose, galactose, mannose and sorbose, trioses, tetroses, heptoses, and octoses), disaccharide (e.g., sucrose, maltose, lactose and trehalose) or oligosaccharide or mixture thereof with a C₄-C₂₂ fatty acid(s)(e.g., saturated fatty acids such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid and stearic acid, and unsaturated fatty acids such as palmitoleic acid, oleic acid, elaidic acid, erucic acid and linoleic acid), or steroidal esters); alkyl, aryl, or cyclic ethers having 2-30 carbon atoms (e.g., diethyl ether, tetrahydrofuran, dimethyl isosorbide, diethylene glycol monoethyl ether); glycofurol (tetrahydrofurfuryl alcohol polyethylene glycol ether); ketones having 3-30 carbon atoms (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone); aliphatic, cycloaliphatic or aromatic hydrocarbons having 4-30 carbon atoms (e.g., benzene, cyclohexane, dichloromethane, dioxolanes, hexane, n-decane, n-dodecane, hexane, sulfolane, tetramethylenesulfon, tetramethylenesulfoxide, toluene, dimethylsulfoxide (DMSO), or tetramethylenesulfoxide); oils of mineral, vegetable, animal, essential or synthetic origin (e.g., mineral oils such as aliphatic or wax-based hydrocarbons, aromatic hydrocarbons, mixed aliphatic and aromatic based hydrocarbons, and refined paraffin oil, vegetable oils such as linseed, tung, safflower, soybean, castor, cottonseed, groundnut, rapeseed, coconut, palm, olive, corn, corn germ, sesame, persic and peanut oil and glycerides such as mono-, di- or triglycerides, animal oils such as fish, marine, sperm, cod-liver, haliver, squalene, squalane, and shark liver oil, oleic oils, and polyoxyethylated castor oil); alkyl or aryl halides having 1-30 carbon atoms and optionally more than one halogen substituent; methylene chloride; monoethanolamine; petroleum benzin; trolamine; omega-3 polyunsaturated fatty acids (e.g., alpha-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, or docosahexaenoic acid); polyglycol ester of 12-hydroxystearic acid and polyethylene glycol (Solutol® HS-15, from BASF, Ludwigshafen, Germany); polyoxyethylene glycerol; sodium laurate; sodium oleate; or sorbitan monooleate.

Other pharmaceutically acceptable solvents for use in the invention are well known to those of ordinary skill in the art, and are identified in The Chemotherapy Source Book (Williams & Wilkens Publishing), The Handbook of Pharmaceutical Excipients, (American Pharmaceutical Association, Washington, D.C., and The Pharmaceutical Society of Great Britain, London, England, 1968), Modern Pharmaceutics, (G. Banker et al., eds., 3d ed.)(Marcel Dekker, Inc., New York, N.Y., 1995), The Pharmacological Basis of Therapeutics, (Goodman & Gilman, McGraw Hill Publishing), Pharmaceutical Dosage Forms, (H. Lieberman et al., eds.,)(Marcel Dekker, Inc., New York, N.Y., 1980), Remington's Pharmaceutical Sciences (A. Gennaro, ed., 19th ed.)(Mack Publishing, Easton, Pa., 1995), The United States Pharmacopeia 24, The National Formulary 19, (National Publishing, Philadelphia, Pa., 2000), A. J. Spiegel et al., and Use of Nonaqueous Solvents in Parenteral Products, JOURNAL OF PHARMACEUTICAL SCIENCES, Vol. 52, No. 10, pp. 917-927 (1963).

DEFINITIONS

The terms “hydrocarbon” and “hydrocarbyl” as used herein describe organic compounds or radicals consisting exclusively of the elements carbon and hydrogen. These moieties include alkyl, alkenyl, alkynyl, and aryl moieties. These moieties also include alkyl, alkenyl, alkynyl, and aryl moieties substituted with other aliphatic or cyclic hydrocarbon groups, such as alkaryl, alkenaryl and alkynaryl. Unless otherwise indicated, these moieties preferably comprise 1 to 20 carbon atoms.

The “substituted hydrocarbyl” moieties described herein are hydrocarbyl moieties which are substituted with at least one atom other than carbon, including moieties in which a carbon chain atom is substituted with a hetero atom such as nitrogen, oxygen, silicon, phosphorous, boron, sulfur, or a halogen atom. These substituents include halogen, heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, protected hydroxy, keto, acyl, acyloxy, nitro, amino, amido, nitro, cyano, thiol, ketals, acetals, esters and ethers.

The term “heteroatom” shall mean atoms other than carbon and hydrogen.

The “heterosubstituted methyl” moieties described herein are methyl groups in which the carbon atom is covalently bonded to at least one heteroatom and optionally with hydrogen, the heteroatom being, for example, a nitrogen, oxygen, silicon, phosphorous, boron, sulfur, or halogen atom. The heteroatom may, in turn, be substituted with other atoms to form a heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, protected hydroxy, oxy, acyloxy, nitro, amino, amido, thiol, ketals, acetals, esters or ether moiety.

The “heterosubstituted acetate” moieties described herein are acetate groups in which the carbon of the methyl group is covalently bonded to at least one heteroatom and optionally with hydrogen, the heteroatom being, for example, a nitrogen, oxygen, silicon, phosphorous, boron, sulfur, or halogen atom. The heteroatom may, in turn, be substituted with other atoms to form a heterocyclo, alkoxy, alkenoxy, alkynoxy, aryloxy, hydroxy, protected hydroxy, oxy, acyloxy, nitro, amino, amido, thiol, ketals, acetals, esters or ether moiety.

Unless otherwise indicated, the alkyl groups described herein are preferably lower alkyl containing from one to eight carbon atoms in the principal chain and up to 20 carbon atoms. They may be straight or branched chain or cyclic and include methyl, ethyl, propyl, isopropyl, butyl, hexyl and the like.

Unless otherwise indicated, the alkenyl groups described herein are preferably lower alkenyl containing from two to eight carbon atoms in the principal chain and up to 20 carbon atoms. They may be straight or branched chain or cyclic and include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, hexenyl, and the like.

Unless otherwise indicated, the alkynyl groups described herein are preferably lower alkynyl containing from two to eight carbon atoms in the principal chain and up to 20 carbon atoms. They may be straight or branched chain and include ethynyl, propynyl, butynyl, isobutynyl, hexynyl, and the like.

The terms “aryl” or “ar” as used herein alone or as part of another group denote optionally substituted homocyclic aromatic groups, preferably monocyclic or bicyclic groups containing from 6 to 12 carbons in the ring portion, such as phenyl, biphenyl, naphthyl, substituted phenyl, substituted biphenyl or substituted naphthyl. Phenyl and substituted phenyl are the more preferred aryl.

The terms “halogen” or “halo” as used herein alone or as part of another group refer to chlorine, bromine, fluorine, and iodine.

The terms “heterocyclo” or “heterocyclic” as used herein alone or as part of another group denote optionally substituted, fully saturated or unsaturated, monocyclic or bicyclic, aromatic or nonaromatic groups having at least one heteroatom in at least one ring, and preferably 5 or 6 atoms in each ring. The heterocyclo group preferably has 1 or 2 oxygen atoms, 1 or 2 sulfur atoms, and/or 1 to 4 nitrogen atoms in the ring, and may be bonded to the remainder of the molecule through a carbon or heteroatom. Exemplary heterocyclo include heteroaromatics such as furyl, thienyl, pyridyl, oxazolyl, pyrrolyl, indolyl, quinolinyl, or isoquinolinyl and the like. Exemplary substituents include one or more of the following groups: hydrocarbyl, substituted hydrocarbyl, keto, hydroxy, protected hydroxy, acyl, acyloxy, alkoxy, alkenoxy, alkynoxy, aryloxy, halogen, amido, amino, nitro, cyano, thiol, ketals, acetals, esters and ethers.

The term “heteroaromatic” as used herein alone or as part of another group denote optionally substituted aromatic groups having at least one heteroatom in at least one ring, and preferably 5 or 6 atoms in each ring. The heteroaromatic group preferably has 1 or 2 oxygen atoms, 1 or 2 sulfur atoms, and/or 1 to 4 nitrogen atoms in the ring, and may be bonded to the remainder of the molecule through a carbon or heteroatom. Exemplary heteroaromatics include furyl, thienyl, pyridyl, oxazolyl, pyrrolyl, indolyl, quinolinyl, or isoquinolinyl and the like. Exemplary substituents include one or more of the following groups: hydrocarbyl, substituted hydrocarbyl, keto, hydroxy, protected hydroxy, acyl, acyloxy, alkoxy, alkenoxy, alkynoxy, aryloxy, halogen, amido, amino, nitro, cyano, thiol, ketals, acetals, esters and ethers.

The term “acyl,” as used herein alone or as part of another group, denotes the moiety formed by removal of the hydroxyl group from the group —COOH of an organic carboxylic acid, e.g., RC(O)—, wherein R is R¹, R¹⁰—, R¹R²N—, or R¹S—, R¹ is hydrocarbyl, heterosubstituted hydrocarbyl, or heterocyclo, and R² is hydrogen, hydrocarbyl or substituted hydrocarbyl.

Having described the invention in detail, it will be apparent that modifications and variations are possible without departing the scope of the invention defined in the appended claims. Furthermore, it should be appreciated that all examples in the present disclosure are provided as non-limiting examples.

The following examples illustrate the invention.

EXAMPLES

The following non-limiting examples are provided to further illustrate the present invention. It should be appreciated by those of skill in the art that the techniques disclosed in the examples that follow represent approaches the inventors have found function well in the practice of the invention, and thus can be considered to constitute examples of modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments that are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

Example 1 Microwave Assisted Synthesis of Highly Substituted Optically Active Aminomethylated 2-Pyridones

In order to obtain the nitriles as amine precursors, brominated 2-pyridones 5a-c were prepared in excellent yields (Scheme 1) using bromine in AcOH.²³ Various cyanodehalogenation procedures employing transition metal catalysts, e.g. palladium catalyzed reactions utilizing zinc cyanide as the cyanide source have worked well with aryl halides.^(24,25) Unfortunately, the brominated 2-pyridone 5a was not consumed in these reactions, a fact that might be due to poisoning of the catalyst by the sulfur containing starting material. As a consequence, the attention was turned to the original Rosenmund von Braun cyanation employing CuCN in refluxing DMF and this time the desired cyanosubstituted 2-pyridones were obtained. Still, the long reaction times and the rather harsh work up procedure were not ideal resulting in low and irreproducible yields. Recent reports of alternative cyanodehalogenation reactions performed on aryl halides have shown that microwave assisted organic synthesis, MAOS, can improve this reaction significantly.²⁵⁻²⁸ Therefore, it was investigated if this technology would be beneficial also for the Rosenmund Von Braun cyanodehalogenation. In the first attempts, 2-pyridone 5a and CuCN were dissolved in DMF and heated to 200° C. for 10 minutes in a microwave apparatus. Although product was formed, the yields were still low (<30%) and a lot of unconsumed starting material was left. Extending the reaction time to 20 minutes gave more product but also significant amounts of byproducts were formed. Fortunately by increasing the temperature to 220° C. and switching the solvent to N-methyl-2-pyrrolidinone, NMP, the cyano substituted 2-pyridone 6a was obtained without detecting any competing side reaction. However, the isolated yields did not reflect the encouraging TLC and LCMS data. The commonly applied work up procedures for the Rosenmund von Braun reaction are often harsh, e.g. heating with HCl and FeCl₃ ^(,17) which clearly affected the total yield and was also a concern regarding the risk of racemisation. Therefore, after trying different extraction procedures with unsatisfactory outcomes, most of the solvent NMP was lyophilized from water. This was followed by thorough extraction of the remaining solid with CH₂Cl₂, which proved critical to obtain good overall yields. Final purification with column chromatography resulted in cyano-substituted 2-pyridones 6a-c (Scheme 1) in very good yields taking into account the presence of the sterically demanding naphtyl substituent in 5a and 5b.

The remaining step to the desired primary amines was the reduction of the nitrile. To accomplish this transformation one had to take into account some constrains. First, sulfur-assisted NaBH₄ reduction of carboxylic acid esters has been reported²⁹ indicating that one might experience selectivity problems and over reduction to the corresponding alcohol. Secondly, Padwa and co workers have shown that transition metal catalyzed hydrogenation reactions at high pressure (90 psi) saturates the 2-pyridone skeleton.²³ Encouraged by a previous good experience in using PdO in a selective dehalogenation of iodopyridone 5d at atmospheric pressure, hydrogenation was utilized in the initial attempts to reduce the nitrile. Unfortunately, hydrogenations at atmospheric pressure using various catalysts e.g. PdO, Pd/C³⁰ and PtO₂ ³¹ as well as different sources of hydrogen (hydrogen gas or ammonium formate) or elevated pressure at 50 psi all proved unsuccessful. Pd—S/C³² and Rh/C³³ were also applied to investigate whether the low reactivity could be explained by the aforementioned problem with poisoning of the catalyst, but without success. Now several electrophilic reducing agents that had been reported as suitable reducing agents for nitriles such as N-Ethyl-N-isopropylaniline-borane (BACH-EI™),^(34,35) AlH₃.NMe₂Et³⁷ and BH₃.Me₂S (BMS)³⁸ were tested. Again, the cyano group remained intact using both BACH-EI™ and AlH₃NMe₂Et, yet in the latter case the methyl ester was reduced to the corresponding alcohol according to LC-MS. The most promising result was achieved with the BMS complex in THF, where traces of the desired amine could be detected after several hours at room temperature. Refluxing overnight gave a substantial increase of product formation albeit this also yielded considerable amounts of byproducts. With the intention to improve the unsatisfactory yields and reaction times, microwave irradiation was studied as an alternative source of heating. Delightfully, this gave complete conversion of the hitherto almost inert cyano functionality in 60 seconds at 100° C. and primary amines 7a-c were obtained in good yields (Scheme 1). The optical purity, however, continued to deteriorate also during this transformation and the enantiomeric excess for primary amine 7b was only 8%.

To introduce symmetrical dialkylamines the renowned Mannich reaction was employed, a classical method known since the early 1900' s,³⁹ often mentioned as one of the most important C—C bond forming reactions in organic chemistry.⁴⁰ Initial efforts using aqueous formaldehyde and protic solvents proved unfruitful as no aminomethylated product could be detected. However, switching to paraformaldehyde and dried aprotic solvents gave some product, still the yields were poor and a lot of unidentified byproducts were formed. These well known limitations of the Mannich reaction could possibly be diminished by shortening the reaction times and encouraged by the results from both the cyanodehalogenation and the borane dimethyl sulfide reduction of the nitriles, microwave irradiation was applied also in this reaction. Disappointingly, initial studies resulted in poor yields, at the best 28%. This could be due to slow formation of the in situ generated iminium salt, allowing competing side reactions to occur. To avoid these problems preformed methylene iminium salts were used, giving a higher concentration of the reactive species. Thus, commercially available Eschenmoser's salt (I⁻Me₂N⁺═CH₂) and pyridone 4c were irradiated for 9 minutes in 1,2-dichloroethane at 160° C. This improved the result substantially as 8a could be isolated in 78% yield. The use of preformed iminiumsalts is a well proven strategy in the Mannich reaction often known to shorten reaction times and increase yields.⁴⁰ Several methods for their preparation are available⁴¹ and N,N-morpholine- and N,N-dimethylmethyleneammoniumchloride were prepared according to published procedures by cleavage of aminals with acetylchloride.⁴² The aminals were conveniently synthesized by condensing the amine of choice with formaldehyde under aqueous conditions.⁴³ The methyleneammonium chloride salts proved effective and compounds 8a and 8b were isolated in 92 and 93% respectively (Table 1, entry 1 and 2). With these excellent results in hand, the microwave assisted Mannich reaction was now applied on the sterically more demanding 2-pyridones 4a,b, which required another portion of reactant and heating for an additional 400 s to be completed. Bearing in mind the pronounced steric impact of the CH₂-naphtyl substituent R² in 4a,b (Table 1) the isolated yields for 8c-f (48-66%) were satisfying. It has previously been observed that the dimethylmethyleneammonium salt is less reactive than the corresponding morpholineammonium salt.⁴¹ This was also confirmed by the results obtained in this study (Table 1, entry 3 and 4). Besides resulting in good to excellent yields, this microwave assisted method offers a much faster reaction, 7-14 minutes compared to >22 hours for earlier published procedures.^(19,20) Moreover, in contradiction to what was observed for the previously described microwave-assisted cyanation and reduction step, the optical purity was not affected as much during this transformation and tertiary amine 8f was obtained with an ee of 75% (compared to 79% ee for the starting material 4b).

TABLE 1 Microwave Assisted Mannich Reaction on Substituted 2-pyridones

en- pro- yield try R¹ R² R³ time (s) duct (%)^(a) 1 Phenyl methyl NMe₂ 400 8a 92 2 Phenyl methyl morpholine 400 8b 93 3 Phenyl CH₂-1-naphtyl NMe₂ 400*2^(b) 8c 48 4 Phenyl CH₂-1-naphtyl morpholine 400*2^(b) 8d 64 5 Cyclopropyl CH₂-1-naphtyl NMe₂ 400*2^(b) 8e 55 6 Cyclopropyl CH₂-1-naphtyl morpholine 400*2^(b) 8f^(c) 66 ^(a)Yield of the purified product. ^(b)An additional amount of 1.1 eq iminium salt was added. ^(c)The enantiomeric excess was 75% (compared to 79% ee for the starting material 4b) as determined by chiral HPLC.

Example 2

All reactions were carried out under an inert atmosphere with dry solvents under anhydrous conditions, unless otherwise stated. CH₂Cl₂ was freshly distilled from calcium hydride, THF was freshly distilled from potassium and N-methyl-2-pyrrolidinone (NMP) was dried over 3A molecular sieves.

All microwave reactions were carried out in a monomode reactor using Smith Process Vials™ (0.5-2.0 or 2.0-5.0 mL filling volume) sealed with Teflon septa and an aluminum crimp top.

TLC was performed on Silica Gel 60 F₂₅₄ (Merck) using UV light detection and staining with a solution of phosphomolybdic acid and cerium (IV) sulfate in 6% aqueous sulfuric acid or ninhydrin (0.2% in EtOH) and the compounds were visualized upon heating. Flash column chromatography (eluents given in brackets) employed normal phase silica gel (Matrex, 60 A, 35-70 μm, Grace Amicon). Ion-exchange resin (Amberlyst 15, H⁺-form, 20-50 mesh) was washed with MeOH prior to use. Organic extracts were dried over sodium sulphate before being concentrated. The ¹H and ¹³C NMR spectra were recorded at 298 K with a Bruker DRX-400 spectrometer in CDCl₃ [residual CHCl₃ (δ_(H) 7.26 ppm) or CDCl₃ (δ_(c) 77.0 ppm) as internal standard] or MeOH [residual CD₂HOD (δ_(H) 3.31 ppm) or CD₃OD (δ_(c) 49.0 ppm) as internal standard]. IR spectra were recorded on an ATI Mattson Genesis Series FTIR™ spectrometer. Optical rotations were measured with a Perkin-Elmer 343 polarimeter at 20° C. High-resolution mass spectra (EI or FAB) were recorded on a JEOL JMS-SX 102 mass spectrometer. Mass spectra of compound 7c were recorded on a Waters micromass ZG using electrospray (ES⁺).

(3R)-6-Bromo-7-naphthalen-1-ylmethyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (5a). Br₂ (110 μL, 2.1 mmol) was added dropwise to a stirred solution of 4a (1.0 g, 2.3 mmol) in AcOH (40 mL) at rt. After stirring for 10 min the reaction mixture was concentrated. Purification by silica gel chromatography (heptane:EtOAc, 1:1) gave 5b as a white foam (1.1 g, 93%): [α]_(D)−140 (c 1.0, CHCl₃); IR λ 2921, 2850, 1747, 1654, 1581, 1467, 1357, 1224 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.83 (dd, J=7.8, 1.6, 1H), 7.76-7.69 (m, 2H), 7.48-7.32 (m, 3H), 7.20-6.94 (m, 6H), 5.78 (dd, J=8.6, 2.6, 1H), 4.38-4.24 (m, 2H), 3.89 (s, 3H), 3.73 (dd, J=11.8, 8.6, 1H), 3.50 (dd, J=11.8, 2.6, 1H); ¹³C NMR (100 MHz, CDCl₃) δ168.1, 157.7, 152.2, 146.2, 136.1, 133.6, 132.5, 131.5, 129.7, 129.2, 128.7, 128.6 (broad and splitted), 128.5, 127.0, 125.9, 125.5, 125.4, 124.4, 122.8, 117.0, 114.4, 64.9, 53.5, 37.2, 31.7; HRMS (FAB+) calcd for C₂₇H₂₀BrNO₃S 506.0426, obsd 506.0427.

6-Bromo-7-(naphtalen-1-ylmethyl)-5-oxo-8-cyclopropyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (5b). Br₂ (28 μL, 0.54 mmol) was added dropwise to a stirred solution of 4b (200 mg, 0.51 mmol) in AcOH (6 mL) at rt. After stirring for 30 min the reaction was quenched with 10% aqueous Na₂S₂O₅ and the solution was extracted with CH₂Cl₂. The organic layers were washed with 10% aqueous NaHCO₃ and brine and the resulting aqueous layers were combined and re-extracted with CH₂Cl₂. The combined organic layers were dried (Na₂SO₄), filtered and concentrated. Purification by silica gel chromatography (heptane:EtOAc, 1:4) gave 5b as a white foam (217 mg, 90%). [α]_(D)−177 (c 1.0, CHCl₃); IR λ 2996, 2950, 2356, 1752, 1639, 1209, 790; ¹H NMR (400 MHz, CDCl₃) 8.16 (d, J=8.2 Hz, 1H), 7.90 (d, J=8.1 Hz, 1H), 7.74 (d, J=8.4 Hz, 1H), 7.64-7.51 (m, 2H), 7.31 (t, 1H), 6.86 (d, J=6.9 Hz, 1H), 5.72 (dd, J=6.2, 2.5 Hz, 1H), 4.88-4.74 (m, 2H), 3.85 (s, 3H), 3.72 (dd, J=11.8, 8.7 Hz, 1H), 3.57-3.51 (dd, J=9.3, 2.4 Hz, 1H), 1.44-1.36 (m, 1H), 0.73-0.63 (m, 2H); 0.59-0.50 (m, 2H); ¹³C NMR (100 MHz, CDCl₃) 168.3, 157.6, 154.4, 146.6, 133.8, 132.4, 131.8, 128.9, 127.1, 126.2, 125.7, 125.6, 123.8, 122.9, 114.7, 114.4, 64.0, 53.4, 36.6, 31.6, 12.2, 7.7, 7.3; HRMS (FAB+) calcd for C₂₃H₂₁BrNO₃S 470.0420, obsd 470.0439.

(3R)-6-Bromo-7-methyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (5c). By following the procedure described for the preparation of 5a from 4a, 4c (400 mg, 1.3 mmol) gave 5c as a white foam (500 mg, 98%): [α]_(D)−213 (c 1.0, CHCl₃); IR λ 2998, 2950, 1745, 1639, 1579, 1471, 1429, 1211 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ7.46-7.32 (m, 3H), 7.24-7.15 (m, 2H), 5.67 (dd, J=8.6, 2.4, 1H), 3.80 (s, 3H), 3.67 (dd, J=11.7, 8.6, 1H), 3.42 (dd, J=11.8, 2.4, 1H), 2.10 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ168.1, 157.2, 150.4, 145.1, 136.7, 129.9, 129.6, 128.9, 128.8, 128.4, 116.2, 112.5, 64.6, 53.3, 31.6, 22.1; HRMS (FAB+) calcd for C₁₆H₁₅BrNO₃S 378.9956, obsd 378.9947.

(3R)-6-lodo-7-naphthalen-1-ylmethyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (5d). N-Iodosuccinimide (125 mg, 0.56 mmol) was added to a stirred solution of 4a (100 mg, 0.23 mmol) in AcOH (1 mL) and TFA (50 μl) at rt. After stirring for 24 hours the reaction mixture was poured on ice water and neutralized with aqueous saturated NaHCO₃. The precipitate was filtered off and purified by silica gel chromatography (heptane:EtOAc, 1:1) giving 5d as a pale orange solid (97 mg, 78%): [α]_(D) 176 (c 0.65, CHCl₃); IR λ 2360, 2344, 1747, 1635, 1570, 1458, 1211, 1151, 993 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.82 (d, J=7.8, 1H), 7.71 (m, 2H), 7.48-7.31 (m, 3H), 7.21-7.01 (m, 5H), 6.97 (d, J=7.5, 1H), 5.77 (dd, J=8.7, 2.4, 1H), 4.42-4.28 (m, 2H), 3.87 (s, 3H), 3.71 (dd, J=11.8, 8.7, 1H), 3.43 (dd, J=11.8, 2.4, 1H); ¹³C NMR (100 MHz, CDCl₃) δ168.1, 158.7, 156.5, 147.6, 136.3, 133.5, 132.5, 131.5, 129.6, 129.1, 128.6, 128.5 (broad and splitted), 128.3, 127.0, 125.8, 125.5, 125.3, 124.5, 122.7, 117.1, 94.3, 65.2, 53.4, 42.0, 31.7; HRMS (FAB+) calcd for C₂₆H₂₁ INO₃S 554.0287, obsd 554.0303.

(3R)-6-Cyano-7-naphthalen-1-ylmethyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (6a). CuCN (120 mg, 1.3 mmol) was added to a stirred solution of 5a (150 mg, 0.30 mmol) in NMP (1.0 mL) at rt. The reaction mixture was heated at 220° C. for 20 min using microwave irradiation and the solvent was then removed by lyophilisation from deionised water. The residue was thoroughly extracted with CH₂Cl₂, dried and concentrated. Purification by silica gel chromatography (heptane:EtOAc, 1:1) gave 6a as a white foam (110 mg, 82%):[α]_(D)−83 (c 1.0, CHCl₃); IR λ 3012, 2956, 2217, 1751, 1654, 1486, 1442, 1369 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.79 (d, J=7.8, 1H), 7.70 (d, J=8.1, 1H), 7.62 (d, J=8.2, 1H), 7.47-7.29 (m, 3H), 7.19-6.92 (m, 5H), 6.87 (d, J=7.3, 1H), 5.79 (dd, J=8.9, 2.3, 1H), 4.41-4.27 (m, 2H), 3.89 (s, 3H), 3.75 (dd, J=11.9, 8.9, 1H), 3.52 (dd, J=11.9, 2.3, 1H); ¹³C NMR (100 MHz, CDCl₃) δ 167.6, 160.7, 158.7, 155.2, 134.4, 133.6, 132.4, 131.4, 129.7, 129.2, 128.8 (broad and splitted), 128.6, 127.6, 126.1, 125.7, 125.3, 125.2, 122.7, 117.1, 115.2, 101.3, 64.4, 53.7, 35.3, 31.8; HRMS (EI+) calcd for C₂₇H₂₀N₂O₃S 452.1195, obsd 452.1192.

6-Cyano-7-(naphtalen-1-ylmethyl)-5-oxo-8-cyclopropyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (6b). By following the procedure described for the preparation of 6a from 5a, 5b (100 mg, 0.21 mmol) gave 6b as a white foam (78 mg, 88%). [α]_(D)−44 (c 1.0, CHCl₃); IR λ 3004, 2954, 2360, 2213, 1747, 1644, 1481, 1213, 1164, 792; ¹H NMR (400 MHz, CDCl₃) 8.12 (d, J=8.2 Hz, 1H), 7.89 (d, J=7.9 Hz, 1H), 7.75 (d, J=8.7 Hz, 1H), 7.62-7.51 (m, 2H), 7.34 (t, 1H), 6,89 (d, J=7.1 Hz, 1H) 5.74 (dd, J=6.7, 2.2 Hz, 1H), 4.83-4.70 (m, 2H), 3.86 (s, 3H), 3.76 (dd, J=9.0, 2.9 Hz, 1H), 3.58 (dd, J=9.8, 2.2 Hz, 1H), 1.27-1.21 (m, 1H), 0.69-0.65 (m, 2H); 0.55-0.53 (m, 2H): ¹³C NMR (100 MHz, CDCl₃) (167.7, 162.9, 158.6, 155.6, 133.8, 132.4, 131.7, 128.9, 127.6, 126.4, 125.9, 125.5, 124.1, 122.8, 115.2, 114.5, 101.7, 63.5, 53.6, 34.8, 31.7, 11.3, 7.7, 7.2; HRMS (FAB+) calcd for C₂₄H₂₁N₂O₃S 417.1267, obsd 417.1289.

(3R)-6-Cyano-7-methyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (6c). By following the procedure described for the preparation of 6a from 5a, 5c (150 mg, 0.39 mmol) gave 6c as a pale yellow foam (110 mg, 86%): [α]_(D)-161 (c 1.0, CHCl₃); IR λ 3012, 2956, 2215, 1749, 1648, 1440, 1365, 1257,1216 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ7.50-7.39 (m, 3H), 7.25-7.18 (m, 2H), 5.72 (dd, J=8.8, 2.3, 1H), 3.85 (s, 3H), 3.72 (dd, J=11.9, 8.8, 1H), 3.51 (dd, J=11.9, 2.3, 1H), 2.21 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ167.6, 158.8, 158.4, 154.3, 135.0, 129.7, 129.5, 129.1 (splitted), 128.9, 116.5, 115.4, 99.5, 64.1, 53.5, 31.7, 20.0; HRMS (FAB+) calcd for C₁₇H₁₅N₂O₃S 327.0803, obsd 327.0805.

(3R)-6-Aminomethyl-7-naphthalen-1-ylmethyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (7a). BH₃.Me₂S (250 μL, 2M in THF, 0.5 mmol) was added dropwise to a solution of 6a (50 mg, 0.11 mmol) in dry THF (4 mL) at rt. The reaction vessel was sealed and heated for 60 s at 100° C. using microwave irradiation. The reaction mixture was cooled to room temperature, diluted with CH₂Cl₂, poured onto ice-cold aqueous HCl (1M) and agitated. The pH was then adjusted to ˜10 with 2M aqueous NaOH and the aqueous layer was extracted with CH₂Cl₂. The combined organic layers were dried and concentrated. The crude product was dissolved in MeOH and swirled with Amberlyst 15. The solid phase was transferred to a filtration funnel and washed with MeOH. The product was released by addition of 10% NH₃ in MeOH and eluted with MeOH. Concentration of the filtrate gave 7a as a yellow solid (36 mg, 72%): [α]_(D)−44 (c 0.25, CHCl₃); IR λ 2958, 2854, 1747, 1631, 1492, 1440, 1259, 1214 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ7.83 (d, J=8.2, 1H), 7.78 (d, J=8.1, 1H), 7.71 (d, J=8.7, 1H), 7.54-7.00 (m, 9H), 5.74 (dd, J=8.6, 2.7, 1H), 4.25-4.11 (m, 2H), 3.96-3.51 (m, 8H), 3.48 (dd, J=11.8, 2.7, 1H); ¹³C NMR (100 MHz, CDCl₃) δ168.1, 161.3, 153.5, 148.9, 135.8, 133.8, 133.6, 131.2, 129.7, 129.3, 128.7 (splitted), 128.5 (splitted), 127.3, 126.3, 125.9, 125.5, 124.4, 123.2, 118.4, 116.6, 64.2, 53.6, 38.0, 33.2, 31.7; HRMS (FAB+) calcd for C₂₇H₂₄N₂NaO₃S 479.1405, obsd 479.1405.

(3R)-6-Aminomethyl-8-cyclopropyl-7-naphthalen-1-ylmethyl-5-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (7b). By following the procedure described for the preparation of 7a from 6a, 6b (46 mg, 0.11 mmol) gave 7b as a yellow solid (33 mg, 73%): [α]_(D)−64 (c 0.25, CHCl₃); IR X 2952, 1747, 1631, 1569, 1504, 1259, 1214 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ8.18 (d, J=8.2, 1H), 7.94-7.27 (m, 5H), 6.81 (d, J=6.8, 1H), 5.67 (d, J=7.3, 1H), 4.77-4.56 (m, 2H), 3.96-3.31 (m, 9H), 1.40 (m, 1H), 0.76-0.31 (m, 4H); ¹³C NMR (100 MHz, CDCl₃) δ168.3, 161.1, 155.6149.5, 133.7, 133.7, 131.6, 128.7, 127.3, 126.4, 126.0, 125.5, 123.8, 123.4, 116.9, 115.7, 63.4, 53.5, 37.6, 32.6, 31.6, 11.8, 7.2, 7.1; HRMS (FAB+) calcd for C₂₄H₂₅N₂O₃S 421.1586, obsd 421.1593.

(3R)-6-Aminomethyl-7-methyl-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (7c). By following the procedure described for the preparation of 7a from 6a, 6c (36 mg, 0.11 mmol) gave 7c as a yellow solid (27 mg, 67%): [α]_(D)−110 (c 0.13, CHCl₃); IR λ 2956, 1747, 1631, 1575, 1490, 1442, 1216 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ7.49-7.30 (m, 3H), 7.25-7.15 (m, 2H), 5.64 (dd, J=8.5, 2.4, 1H), 3.92-3.69 (m, 7H), 3.62 (dd, J=11.5, 8.6, 1H), 3.41 (dd, J=11.6, 2.3, 1H), 2.02 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 168.8, 161.1, 152.0, 147.8, 136.4, 130.0, 129.9, 129.0, 128.9, 128.5, 118.0, 115.3, 64.0, 53.6, 37.9, 31.7, 18.0; MS (ES+) calcd 331 for C₁₇H₂₀N₂O₃S, obsd 331.

6-Dimethylamine-7-(methyl)-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8a). N,N-Dimethylmethyleneammoniumchloride (140 mg, 1.50 mmol) was added to a stirred solution of 4c (200 mg, 0.66 mmol) in dry 1,2-dichloroethane (3 mL) at rt. The reaction vessel was sealed and heated for 400 s at 140° C. using microwave irradiation. The reaction mixture was then diluted with CH₂Cl₂, MeOH and concentrated. Purification by silica gel chromatography (ethylacetate→ethylacetate 2,5% triethylamine) gave 8a as a white foam (219 mg, 92%). [α]_(D)−163 (c 1.0, CHCl₃); IR λ 2939, 2817,1747,1631, 1490,1209, 703; ¹H NMR (400 MHz, CDCl₃) 7.43-7.30 (m, 3H) 7.24-7.16 (m, 2H) 5.64 (dd, J=8.6, 2.5 Hz, 1H) 3.78 (s, 3H) 3.59 (dd, J=11.7, 8.7 Hz, 1H) 3.47 (d, J=12.2 Hz, 1H) 3.38 (dd, J=11.7, 2.5 Hz, 1H) 3.31 (d, J=12.2 Hz, 1H) 2.25 (s, 6H) 2.0 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) 168.6, 161.5, 150.7, 144.2, 137.3 130.0, 129.7, 128.7, 128.6, 127.9, 122.2, 116.7, 64.0, 54.2, 53.1, 45.4, 31.3; 17.5; IR λ 2939, 2817, 1747, 1631, 1490, 1209, 703; HRMS (FAB+) calcd for C₁₉H₂₃N₂O₃S 359.1429, obsd 359.1426.

6-Morpholine-7-(methyl)-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8b). By following the procedure described for the preparation of 8a from N,N-Dimethylmethyleneammoniumchloride and 4c, N,N-Morpholinemethyleneammoniumchloride and 4c (200 mg, 0.66 mmol) gave 8b as a white foam (249 mg, 93%). [α]_(D)−161 (c 1.0, CHCl₃); IR λ 2955, 2850, 2360, 1749, 1631, 1490, 1112, 703; ¹H NMR (400 MHz, CDCl₃) 7.45-7.34 (m, 3H), 7.26-7.20 (m, 2H), 5.67 (dd, J=8.6, 2.6 Hz, 1H), 3.82 (s, 3H), 3.70-3.64 (m, 4H), 3.63-3.53 (m, 2H), 3.46-3.38 (m, 2H), 2.53-2.48 (m, 4H), 2.07 (s, 3H); ¹³C NMR (100 MHz, CDCl₃) 168.5, 161.5, 151.3, 144.4, 137.2, 130.0, 129.8, 128.7, 128.6, 120.0, 121.1, 116.7, 67.1, 64.0, 53.4, 53.1, 31.8, 31.3, 17.5; HRMS (FAB+) calcd for C₂₁H₂₅N₂O₄S 401.1535, obsd 401.1536.

6-Dimethylamine-7-(naphtalen-1-ylmethyl)-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8c). N,N-Dimethylmethyleneammoniumchloride (144 mg, 1.54 mmol) was added to a stirred solution of 4a (300 mg, 0.70 mmol) in dry 1,2-dichloroethane (3 mL) at rt. The reaction vessel was sealed and heated for 140° C. for 400 s using microwave irradiation, more N,N-Dimethylmethyleneammoniumchloride (72 mg, 0.77 mmol) was added, and the reaction mixture was heated for another 400 s at 140° C. The reaction mixture was then diluted with CH₂Cl₂, MeOH and concentrated. Purification by silica gel chromatography (ethylacetate→ethylacetate 2,5% triethylamine) gave 8c as a white foam (148 mg, 48%). [α]_(D)−151 (c 1.0, CHCl₃); IR λ 3048, 2940, 2817, 2767, 1747, 1633, 1490, 790, 701; ¹H NMR (400 MHz, CDCl₃) 7.83-7.77 (m, 2H) 7.67 (d, J=8.2 Hz, 1H) 7.45-7.30 (m, 3H) 7.12-6.99 (m, 6H) 5.76 (dd, J=8.6, 2.6 Hz, 1H) 4.44 (d, J=16 Hz, 1H) 4.32 (d, J=16 Hz, 1H) 3.85 (s, 3H) 3.66 (dd, J=11.8, 8.7 Hz, 1H) 3.44 (dd, J=11.8, 8.7 Hz, 1H) 3.30-3.20 (m, 2H) 2.21 (s, 6H); ¹³C NMR (100 MHz, CDCl₃) 168.5, 161.8 152.2, 145.5, 136.5, 134.5, 133.3, 131.6, 129.8, 129.2, 128.4, 128.3, 128.2, 127.9, 126.7, 125.8, 125.4, 125.3, 124.2, 123.4, 122.8, 117.2, 64.2, 53.9, 53.1, 45.6, 31.8, 31.3; HRMS (FAB+) calcd for C₂₉H₂₉N₂O₄S 485.1893, obsd 485.1866.

6-Morpholine-7-(naphtalen-1-ylmethyl)-5-oxo-8-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8d). N,N-Morpholinemethyleneammoniumchloride (209 mg, 1.54 mmol) was added to a stirred solution of 4a (300 mg, 0.70 mmol) in dry 1,2-dichloroethane (3.2 mL) at rt. The reaction vessel was sealed and heated for 400 s at 140° C. using microwave irradiation, more N,N-Morpholinemethyleneammoniumchloride (105 mg, 0.77 mmol) was added and the reaction mixture was heated for another 400 s at 140° C. The reaction mixture was then diluted with CH₂Cl₂, MeOH and concentrated. Purification by silica gel chromatography (ethylacetate→ethylacetate 2,5% triethylamine) gave 8d as a yellow foam (237 mg, 64%). [α]_(D)−98 (c 1.0, CHCl₃); IR λ 2952, 2846, 1749, 1633, 1490, 1112, 701 cm⁻¹; ¹H NMR (400 MHz, CDCl₃) δ 7.84-7.79 (m, 2H) 7.68 (d, J=8.2 Hz, 1H) 7.46-7.38 (m, 2H) 7.34 (t, 1H) 7.17-7.04 (m, 6H) 5.75 (dd, J=8.6, 2.7 Hz, 1H) 4.49 (d, J=15.9, 1H) 4.34 (d, J=15.9 Hz, 1H) 3.87 (s, 3H) 3.69 (dd, J=11.8, 8.7 Hz, 1H) 3.56-3.50 (m, 4H) 3.46 (dd, J=11.8, 2.7 Hz, 1H) 3.32 (m, 2H) 2.40-2.30 (m, 4H); ¹³C NMR (100 MHz, CDCl₃) δ 168.5, 161.9, 153.1, 145.7, 136.5, 134.8, 133.4, 131.7, 129.9, 129.3, 128.6, 128.4, 128.4, 128.0, 126.7, 125.8, 125.5, 125.4, 124.4, 122.8, 122.3 117.5, 66.9, 64.3, 53.5, 53.2, 53.2, 32.0, 31.3; HRMS (FAB+) calcd for C₃₁H₃₁N₂O₄S 527.1999, obsd 527.2008.

6-Dimethylamine-7-(naphtalen-1-ylmethyl)-5-oxo-8-cyclopropyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8e). By following the procedure described for the preparation of 8c from 4a, 4b (200 mg, 0.51 mmol) gave 8e as a white foam (125 mg, 55%). [α]_(D)−177 (c 1.0, CHCl₃); IR λ 2939 2948, 2817, 2767, 1747, 1633, 1579, 1498, 1211, 792, 773; ¹H NMR (400 MHz, CDCl₃) 8.23 (d, J=8.4 Hz, 1H), 7.86 (d, J=7.8 Hz, 1H) 7.69 (d, J=8.2 Hz, 1H) 7.60-7.48 (m, 2H) 7.31-27 (m, 1H) 6.82 (d, J=6.8 Hz, 1H) 5.69 (dd, J=8.7, 2.5 Hz, 1H) 4.83-4.80 (m, 2H) 3.81 (s, 3H) 3.67 (dd, J=11.8, 8.7 Hz, 1H) 3.48 (dd, J=8.7, 2.6 Hz, 1H) 3.30-3.19 (m, 2H) 2.19 (s, 6H) 1.34-1.24 (m, 1H) 0.63-0.53 (m, 4H); ¹³C NMR (100 MHz, CDCl₃) 168.7, 161.7, 154.9, 145.9, 134.5, 133.5, 131.9, 128.6, 128.6, 126.0, 125.6, 125.5, 123.7, 123.6, 123.0, 114.2, 63.4, 53.7, 53.0, 45.5, 31.2, 31.2, 11.5, 7.2, 7.0; HRMS (FAB+) calcd for C₂₆H₂₉N₂O₃S 449.1893, obsd 449.1887.

6-Morpholine-7-(naphtalen-1-ylmethyl)-5-oxo-8-cyclopropyl-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (8f). By following the procedure described for the preparation of 8d from 4a, 4b (400 mg, 1.02 mmol) gave 8f as a yellow foam (331 mg, 66%). [α]_(D)−110 (c 1.0, CHCl₃); IR λ 2956, 2844, 1749, 1631, 1496, 1110, 792, 773, 728; ¹H NMR (400 MHz, CDCl₃) 8.20 (d, J=8.4 Hz, 1H), 7.87 (d, J=7.5 Hz, 1H) 7.70 (d, J=8.2 Hz, 1H) 7.61-7.48 (m, 2H) 7.29 (t, 1H) 6.84 (d, J=7.1 Hz, 1H) 5.68 (dd, J=8.7, 2.6 Hz, 1H) 4.87-4.78 (m, 2H) 3.82 (s, 3H) 3.69 (dd, J=11.8, 8.7 Hz, 1H) 3.52-3.45 (m, 5H) 3.32 (m, 2H) 2.34 (m, 4H) 1.40-1.32 (m, 2H) 0.68-0.53 (m, 4H); ¹³C NMR (100 MHz, CDCl₃) 168.6, 161.8, 155.5, 146.1, 134.7, 133.5, 131.9, 128.7, 126.6, 126.0, 125.6, 125.4, 123.6, 122.9, 122.4, 114.5, 66.9, 63.4 53.3, 53.1, 52.9, 31.4, 31.2, 11.5, 7.3, 7.0; HRMS (FAB+) calcd for C₂₉H₃₁N₂O₄S 491.1999, obsd 491.1998.

8-Cyclopropyl-6formyl-7-naphthalen-1-ylmethyl-5-oxo-2,3-dihydro-5h-thiazolo[3,2-a]pyridine-3-carboxylic acid methyl ester (2). 1 (500 mg, 1,23 mmol) was quickly added to a stirred solution of Vilsmeier's salt (Cl⁻Me₂N═CHCl) (630 mg, 4.93 mmol) in acetonitrile (10 ml). After refluxing for 3 h the solution was concentrated then diluted with CH₂Cl₂ and quenched with sat NaHCO₃ (aq). The aqueous phase was extracted with CH₂Cl₂ and the combined organic-phases were dried over Na₂SO₄(s) filtered and concentrated. Purification by filtering through a short silica plug (EtOAc) gave 2a as yellow foam (532 mg, 99%).[α]_(D)−16.4°; ¹H-NMR (400 MHz, CDCl₃), 10.39 (s, 1H), 8.19 (d, J=8.3, 1H), 7.86 (d, J=8.1, 1H), 7.69 (d, J=8.3, 1H), 7.59 (t, J=7.6, 1H), 7.52 (t, J=7.4, 1H), 7.27 (t, J=7.7, 1H), 6.77 (d, J=7.0, 1H), 5.75 (dd, J=9.0, 2.6, 1H), 5.21 (d, J=14.8, 1H), 5.09 (d, J=14.8, 1H), 3.87 (s, 3H), 3.69-3.79 (m, 1H), 3.54 (dd, J=12.0, 2.5, 1H), 1.30-1.38 (m, 1H), 0.64-0.75 (m, 2H), 0.50-0.58 (m, 2H); ¹³C-NMR (100 MHz, CDCl₃), 190.7, 168.1, 162.2, 160.8, 156.7, 134.5, 133.6, 132.0, 128.7, 126.7, 126.0, 125.6, 125.3, 123.1, 123.0, 118.9, 115.5, 63.3, 53.4, 31.4, 31.4, 11.1, 7.8, 7.2; IR, 2952, 2362, 2246, 1749, 1635, 1475, 1409, 1216, 1160, 728.

General procedure for reductive anination. 1.0 eq of amine is added to a stirred solution of aldehyde in CH₂Cl₂:MeOH and 3 A mol sieves at 0° C. and is allowed to stir for 30 min. 1.8 eq of Sodium triacetoxyborohydride is then added and the mixture is allowed to attain rt and stir for 3 hours. Washed with sat NaHCO₃ (aq). The aqueous phase is extracted with CH₂Cl₂ and the combined organic-phases were dried over Na₂SO₄(s). Purification by column chromatography yields the aminomethylated 2-pyridones 3a-f.

(3R)-6-(Benzylamino-methyl)-8-cyclopropyl-7-(Naphtalen-1-ylmethyl)-5-oxo-2,3-dihydro-5h-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (3b). ¹H-NMR (400 Mhz, CDCl₃) 8.08 (d, J=8.32 Hz, 1H, ArH), 7.88 (d, J=7.87 Hz, 1H, ArH), 7.71 (d, J=8.14 Hz 1H, ArH), 7.64-7.47 (m, 2H, ArH) 7.35-7.07 (m, 6H, ArH) 6.83 (d, J=6.86 Hz, 1H, ArH), 5.68 (d, J=7.50 Hz, 1H, CHCO₂Me), 4.66 (d, J=16.47 Hz, 1H, Nph-CH₂), 4.57 (d, J=16.47 Hz, 1H, Nph-CH₂) 3.83 (s, 3H, CH₃) 3.77-3.38 (m, 7H, SCH₂, PhCH₂, BnNHCH₂) 1.46-1.33 (m, 1H, CH-cyclopropyl) 0.70-0.44 (m, 4H, CH₂-cyklopropyl) ¹³C-NMR (100 Mhz, CDCl₃) δ 168.67, 161.52, 153.13, 146.01, 139.55, 134.42, 133.61, 131.74, 128.76, 128.21, 128.13, 126.94, 126.81, 126.21, 125.77, 125.50, 124.35, 123.99, 123.04, 114.53, 63.31, 53.46, 53.23, 45.31, 31.93, 31.42, 29.65, 11.79, 7.42, 7.12.

(3R)-8-Cyclopropyl-6-hydroxymethyl-7-(Naphtalen-1-ylmethyl)-5-oxo-2,3-dihydro-5h-thiazolo[3,2-a]pyridine-3-carboxylic Acid Methyl Ester (4). The formylated 2-pyridone 2 (100 mg, 0.239 mmol) was dissolved in tetrahydrofuran (3.30 mL) at 0° C. Then 2M BH₃ DMS THF (0.131 mL, 0.262 mmol) was added dropwise during 15 min. The mixture was then stirred in room temperature during 1 h, quenched with methanol and concentrated twice from methanol. The residue was purified through flash column chromatography (CH₂Cl₂:MeOH, 9:1). Co-concentration from CH₂Cl₂ (×2) resulted in 4 as white foam (80.6 mg, yield: 80%). ¹H-NMR (400 Mhz, CDCl₃) δ 8.16 (d, J=8.23 Hz, 1H, ArH), 7.87 (d, J=7.96 Hz, 1H, ArH), 7.71 (d, J=8.14 Hz 1H, ArH), 7.64-7.48 (m, 2H, ArH) 7.30 (m, 1H, ArH) 6.83 (d, J=6.95 Hz, 1H, ArH), 5.68 (d, J=7.04 Hz, 1H, CHCO2Me), 4.72 (d, J=16.28 Hz, 1H, Nph-CH2), 4.61 (d, J=16.28 Hz, 1H, Nph-CH2) 4.58-4.36 (m, 2H, CH₂OH) 3.84 (s, 3H, CH₃) 3.76-3.62 (m, 2H, SCH₂, OH) 3.60-3.50 (m, 1H, SCH₂) 1.46-1.34 (m, 1H, CH-cyclopropyl) 0.65 (ss, 2H, CH₂-cyklopropyl) 0.51 (ss, 2H, CH₂-cyklopropyl) ¹³C-NMR (100 Mhz, CDCl₃) δ 168.61, 161.87, 152.08, 146.62, 134.11, 133.76, 131.77, 128.94, 127.17, 126.37, 125.92, 125.66, 125.63, 124.26, 122.98, 114.93, 63.27, 58.78, 53.40, 31.77, 31.58, 11.81, 7.53, 7.20.

(3R)-8-Cyclopropyl-7-(Naphtalen-1-ylmethyl)-5-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyridine-3,6-dicarboxylic Acid 3-Methyl Ester (5). To a solution of 2 (100 mg, 0.239 mmol) in dimethylsulfoxide (2.40 mL), NaH2PO4 (66.0 mg, 0.478 mmol), dissolved in water (0.960 mL), was added dropwise at room temperature. The mixture was then kept on ice and NaClO₂ (86.0 mg, 0.956 mmol) dissolved in water (0.480 mL), was added dropwise during 30 min. A white precipitate formed. The reaction mixture was stirred in room temperature for 1 h and then poured into a separation funnel containing ice-cooled 1M HCl. The aqueous phase was extracted with CH₂Cl₂ and the combined organic phases concentrated. The residue was dissolved in H₂O:MeCN, 8:2 and freeze dried to yield 5 as a white powder (102 mg, yield: 98%). ¹H-NMR (400 Mhz, CDCl₃) δ 14.60 (s, 1H, CO₂H), 8.21 (d, J=8.32 Hz, 1H, ArH), 7.85 (d, J=7.68 Hz 1H, ArH), 7.67 (d, J=8.14 Hz, 1H, ArH) 7.61-7.45 (m, 2H, ArH) 7.30-7.21 (m, 1H, ArH), 6.69 (d, J=6.72 Hz, 1H, ArH), 5.78 (d, J=8.42 Hz, 1H, ArH), 5.51 (d, J=14.55 Hz, 1H, Nph-CH₂) 5.37 (d, J=14.55 Hz, 1H, Nph-CH₂) 3.87 (s, 3H, CH₃) 3.82-3.72 (m, 1H, SCH₂) 3.63-3.54 (m, 1H, SCH₂) 1.44-1.32 (m, 1H, CH-cyclopropyl) 0.81-0.64 (m, 2H) 0.56 (sd, 2H, CH₂-cyclopropyl) ¹³C-NMR (100 Mhz, CDCl₃) δ 167.59, 165.24, 165.09, 163.75, 154.33, 134.92, 133.84, 132.16, 128.83, 126.78, 126.15, 125.76, 125.51, 123.40, 123.23, 118.68, 112.72, 64.10, 53.84, 33.35, 31.58, 12.10, 8.35, 7.67.

Example 3 Protocol for Hemagglutination Assay

The Hemagglutination Assay was carried out according to the following steps:

1. The bacterial culture or protein was induced with either IPTG or arabinose for an optimal amount of time.

2. Next, blood was washed with PBS (by adding PBS, spinning, pouring off supernatant, then adding PBS) until the supernatant was clear of red color.

3. The blood was then brought to optical density of 2.0 at a wavelength of 640 nm to absorbance of 1.8-2.0 (PBS was added until the right OD was obtained).

Steps 4 & 5 were completed for bacteria. When proteins were used, these two steps were ignored.

4. The bacteria was brought to optical density of 2.0 at 600 nm to the absorbance of 0.9-1.0 in PBS (the induced culture was spun down first and then brought up in PBS to OD).

5. A total of 3 ml of bacterial culture was spun down in an ependorff tube. The bacterial pellete was then resuspended in 100 micro liter PBS.

6. 25 micro liter of PBS was placed in every well of a V-bottom microtiter plate.

7. Next, 25 micro liters of appropriate bacteria (or protein) was added in the first well of each row. Typically at least triplicate of the same bacteria was used on the same plate.

8. With a multi-channel pipet a 2-fold serial dilution was done of the bacterial culture (or protein) by completing the following steps:

a. the bacteria and PBS were mixed in first well.

b. 25 micro liters were removed and put in the next well;

c. the contents of the wells were mixed;

d. steps b and c were repeated for serial dilution.

9. 25 micro liters of the appropriate blood were added to each row (changing tips in between). The wells were taped lightly to evenly distribute the liquid in the wells.

10. The wells were covered and placed in 4 degree Celcius cold room until the plate was read.

The results of this assay are disclosed in Table A.

Example 4 Infection of Bladder Cells In Vitro (Adherence Assay)

The infection of bladder cells in vitro was carried out according to the following steps:

Preparation of Tissue Culture Cells (Type 5637 Bladder Cell Line)

1. Place 1 ml of RPMI/10% FBS containing 1:20 dilution of 5637 cells in each well of 24 well plate.

2. Place in incubator for 3 days or until confluent growth.

Preparation of Bacterial Cells (Strains NU14 and UTI89)

1. Inoculate 20 ml of LB containing NU14 with a single colony or a loop from a frozen stock to a 250 ml flask.

2. Static growth at 37° C. for 2 days to induce pili production.

3. Harvest cells at 4,000×g for 10 minutes.

4. Resuspend in 5 ml of PBS (−109 cells/ml)

5. Dilute 1:100 in PBS.

Infection of Tissue Culture Cells In Vitro

1. Wash each well with PBS MgCl₂/CaCl₂.

2. Place 1 ml of fresh medium to each well.

3. Add 10 μl of bacterial cells to each well. Triplicate plates.

4. Spin plate at 1800 rpm for 5 minutes.

5. View under 40× to see −2-3 bacterial cells/epithelial cell.

6. Place in lower incubator for 2 hours.

7. Wash two plates 5× with PBS MgCl₂/CaCl₂. Lyse by addition of 0.1% sarkosyl/0.5% glucose/PBS-MgCl₂/CaCl₂ one set and dilute for CFU.

The results of this assay are disclosed in Table A.

Example 5 Biofilm Assay

The Biofilm Assay was carried out according to the following steps:

Day 1 Set Up Biofilm Growth on PVC Plates

1. Sterilize PVC plates (96-well round bottom polyvinyl chloride [PVC] plates; Falcon #353911) and PVC Lids (Falcon #353913) in tissue culture hood under UV irradiation for at least 30 min.

2. Make dilution (from overnight cultures) or suspension (from either colonies on plates or freezer stocks) of bacterial cultures. Make enough of bacterial cultures for the number of wells needed. Bacterial culture need to be very dilute: at least 1:1,000 fold dilution from overnight cultures or a small quantity from colonies or freezer stocks.

3. Add 100 μl of bacterial cultures into each well. Make sure to have 1 well with LB alone as negative control and 1 well without anything for blank.

4. Cover plates with lids and leave plates undisturbed at room temperature for 48 hrs.

Day 3 Assay Biofilm With Crystal Violet Stain

Wash Biofilm Plates

5. Prepare enough PBS (w/out Mg²⁺ Ca²⁺) to wash biofilm plates (need at least 3 L PBS for 1-5 plates). Could use mpH₂O instead of PBS.

6. Get a clean 4 L plastic beaker. Cover the bench with a large piece of absorbent pad.

7. Fill 3 containers (large enough to dip the 96-well plates in) with PBS.

8. Start washing a biofilm plate by dumping out bacterial cultures into the beaker. (Treat contents in this beaker as biohazard. Need to bleach the content before emptying it into drain.)

9. Fill the biofilm plate in the first PBS container and shake off PBS in the beaker. Rinse the biofilm 1× in the first PBS container. Put the biofilm plate into the second PBS container and rinse 2×.

10. Put the biofilm plate in the third PBS container and let sit.

11. Proceed to wash a second biofilm plate if there are any.

12. While the second biofilm plate is in the second container, rinse the first biofilm plate 1× and remove it from PBS. Decant residual PBS by banging the plate on paper towels on the bench. Leave the plate up-side-down on a clean paper towel and let the plate dry.

13. Put the second biofilm plate into the third PBS container and let sit.

14. Proceed to wash a third biofilm plate if applicable.

15. Repeat steps 8-14 until all plates are washed.

16. Let washed biofilm plates air-dry for at least 15 min.

Crystal Violet Stain and Wash

17. Fill 4 containers (large enough to dip the 96-well plates in) with PBS.

18. With a multi-channel pipet, add 125 μl of 1% Crystal Violet (in mpH₂O). Stain biofilm plates sequentially for 10 min. (not more than 15 min). Give at least 2 minute break in-between staining each plates. If more than 4 biofilm plates, might want to consider staining and washing them in batches.

19. Start washing biofilm plates as above.

20. Let the washed plates air-dry for 10 min or so.

Assay Crystal Violet Stain

21. While plates are drying, prepare EtOH:Acetone (80:20) solubilization solution. Need 150 μl/well.

Get new flat-bottom 96-well plates (use ELISA plates; Immunon-4).

Set up the Plate Reader.

22. Add 150 μl of solubilization solution into each well to dissolve stained biofilms. Be sure not to splatter to other wells. Change tips if pipet tips become contaminated with crystal violet.

23. After adding solubilization solution to all wells, transfer 100 μl of the dissolved biofilms to a new flat-bottom plate, except the well intended for blank. Change tips in between transfer. Add 100 μl of fresh solubilization solution into the blank well. P 24. Proceed immediately to the Plate Reader and read the absorbance of the plate at 600 nm.

25. Continue steps 22-24 for each plate.

The results of this assay are disclosed in Table A.

TABLE A Pilicide Data From Assays Adherence Assay Biofilm Assay Compound HA Titer % of Wild Type % of Wild Type NU14 2⁸  100%  100%

C₁₈H₁₉LiN₂O₃S Exact Mass: 350.1276 Mol. Wt.: 350.3611 2⁸ 97.6% 73.1%

C₂₈H₂₅LiN₂O₃S Exact Mass: 476.1746 Mol. Wt.: 476.5157 2⁴ 21.8%  6.9%

C₃₁H₂₈LiN₂O₄S Exact Mass: 531.1930 Mol. Wt.: 531.5710 2⁴ 14.3%  6.8%

C₂₇H₂₇LiN₂O₄S Exact Mass: 482.1852 Mol. Wt.: 482.5203 2³ 12.2%  8.3%

BIBLIOGRAPHY

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1. The amino methylated 2-pyridinone corresponding to Formula VIa or a salt thereof:

wherein R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl or heterocyclo or, in combination with the nitrogen atom to which they are bonded, form a heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen; R₄ and R₅ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl, or heterocyclo, provided at least one of R₄ and R₅ is other than hydrogen; X₅ is —C(H)—; X₃₃ is an electron pair or oxo; X₄₄ is hydrogen or hydrocarbyl; X₅₅ is —CO₂X₅₅₅; and X₅₅₅ is hydrogen, a cation, hydrocarbyl, substituted hydrocarbyl, or heterocyclo.
 2. The amino methylated 2-pyridinone of claim 1 wherein X₄₄ is hydrogen or alkyl.
 3. The amino methylated 2-pyridinone of claim 1 wherein X₅₅₅ is an alkali metal.
 4. The amino methylated 2-pyridinone of claim 1 wherein R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl or heterocyclo, provided at least one of R₂ and R₃ is other than hydrogen.
 5. The amino methylated 2-pyridinone of claim 1 wherein (i) R₂ and R₃ are independently hydrogen, hydrocarbyl, substituted hydrocarbyl or heterocyclo, and (ii) X₄₄ is hydrogen or hydrocarbyl.
 6. The amino methylated 2-pyridinone of claim 1 wherein R₂ is alkyl.
 7. The amino methylated 2-pyridinone of claim 1 wherein R₂ and R₃, in combination with the nitrogen atom to which they are bonded form a heterocyclo.
 8. The amino methylated 2-pyridinone of claim 1 wherein R₄ is alkyl or aryl.
 9. The amino methylated 2-pyridinone of claim 1 wherein R₅ is alkyl.
 10. A compound having the formula

wherein R₁ is phenyl, R₂ is methyl, R₃ is NMe₂ and Me is methyl.
 11. A process for inhibiting adherence of a bacteria to a host cell, the process comprising treating the bacteria with a compound of claim 1 or a salt thereof.
 12. A process for inhibiting adherence of a bacteria to a host cell, the process comprising treating the bacteria with a compound of claim 2 or a salt thereof.
 13. A compound having the formula

wherein R₁ is phenyl, R₂ is —CH₂-1-naphthyl, R₃ is NMe₂, and Me is methyl.
 14. A compound having the formula

wherein R₁ is phenyl, R₂ is —CH₂-1-naphthyl, R₃ is morpholine.
 15. A compound having the formula

wherein R₁ is cyclopropyl, R₂ is —CH₂-1-naphthyl, R₃ is NMe₂ and Me is methyl. 